Grab a cup of coffee! My C4 problem.
01-04-2012, 11:54 AM
#1
Racer
Thread Starter
Grab a cup of coffee! My C4 problem.
Let me start at the beginning .
I was cruising along on I-10 when my Vette started missing and backfiring.
I was able to get off at an exit close by.
I called a tow truck and by the time it arrived the car was running fine.
I took it to a shop the local corvette club
Recommended.
They couldn't find any thing wrong.
It left me stranded again a few days later.
Since I have a Delteq ignition I suspected that's what it was but it checked out fine according to the trouble shooting guide.
It got to where it would turn over but would not start.
After playing around and not getting anywhere I called a shop familiar with the ignition about 70 mi away.
I called a tow truck and the driver asked if it would start.
I told him it hadn't started in a month.
I tried it and the damn thing started!!
The shop had it a week and it kept running.
Finally, it started acting up.
They told me they believed it was a security issue.
I told them I never thought of that.
After waiting a couple of weeks for their
Friend at the local Chevy dealer to confirm their suspicion with some electronic devise, he confirmed that suspicion.
They said I needed to get the security deleted from the chip in the ECU.
I informed them that it was an aftermarket chip from Ed Wright.
I had the shop overnight the chip to Ed because he was getting ready to go racing for a week or so.
The shop called and told me the chip was back in the car and they started it many times and drove it around.
They said it was ready and I went to get the Vette. I was happy!
20 mi later I stopped to wash the car. It started and I let It idle when I saw the tach needle jump and then it quit.
It would start, miss & spit, and quit.
I had just spent over $400.00 and I was furious!
I tried calling the shop and could not get anyone.
I ran the battery down trying to get it to stay running. Hello tow truck.
After waiting over an hour for the tow I tried a jump. The car started and ran fine??
I made it to Cruising the Coast, about 80 mi. away. I drove it around that night and parked it.
The next night when I went to leave the Vette started right up.
I made it about a mile down the road and it started doing the same thing as before. Missing,backfiring etc.
I didn't want to leave it so I kept trying to get it going and it finally did and off we went. This happened about 5 or 6 times. Each time I was about to give up when it would run good and off we would go. It always would turn over.
I'm lucky I didn't blow the heads off it was backfiring so bad! I did blow the insides of my CAT’s.
The pieces were hitting my cousins car behind me.
After I finally got it home I then thought maybe it’s my fuel pump and that’s why it backfired because it was running lean.
I changed the pump and the car started and ran fine.
I thought it was “MAYBE” the answer. It wasn’t!
It quit on the way to fill the tank. I had 5 gallons on board.
After checking everything including my injectors I went again to a different president of a Corvette Club.
He told me about a place which was close by where the guy has been working on Vettes for over 40 years.
I didn’t even know about the place!
Oh by the way. I called Ed Wright and asked him what he thought.
When I told him the problems I was still having he told me in his gruff voice “You didn’t tell me it happens while you were driving. The security issue is only when your car will turn over but won’t start!” That’s more money I threw out the window. Who knew?
Anyway, back to the shop that’s been working on Vettes for 40 years.
I had the car towed (again) to his shop.
In a few hours he said it was my Opti Spark.
At this point I had my suspicions that the Opti was a problem.
In about four hours he called and said the rotor was in pieces. I informed him the DelTeq ignition doesn’t need the rotor. He said I know but these pieces would fly around in there and block the light sensor at times. It sounded logical to me.
He called me and said it’s running fine, he drove it around.
I said great!
When I picked the car up I told him if it runs good for more than two days he’s the Man.
He laughed and said that’s a GM Opti, you won’t have anymore problems.
One mile down the road the car quit!! I could not believe it!! Another $400.00 down the tubes.
When I called him he thought I was kidding him. I told him I wish I was.
While waiting for the “tow truck” I tried numerous times to get it started but it would not even try.
As usual it always turned over.
A few days later he called and said it now appears it’s the ECU.
I say ok,do it!
He sent the ECU off to be checked. The company tells him they found some problems and some corrosion and will repair it.
A couple weeks goes by and I call to find out what’s going on. He tells me he just put the ECU on the car and it would not start and the digital dash was jumping all over the place. NO!!
He said he called the place back and they said to send the ECU back.
He calls me back a couple of weeks later and says well, we got the ECU back. The dash isn’t jumping around. The car starts right up but only stays running for about 10 min. then quits. When will this end?
He says he called the company and they are sending him a brand new ECU.
A few weeks later he calls and said the Vette is running great. Eureka! It’s about time.
Another $500.00 bucks and the car is running great!
I drive it for about 6 miles, got on it about 3 or 4 times through the gears, no problems.
I park it in the garage and didn’t get back to it for over a week.
Just before Christmas I tell the wife let’s go for a ride in the Vette. She says you want me to follow you?
I say Nah it’s fine now.
I should have listened to her as usual. The car started acting up just like it did when it all started and then it quit. It will start missing badly. The tach needle will jump and it will spit and back fire if you try to keep it running by playing with the gas pedal.
When it quit, I just pulled over and called the shop.
I could tell by his voice that he didn’t want to see my car again. He said before he called me to tell me the car was ready he drove it for about 50 miles. I told him that doesn’t mean anything. Everytime I think we’ve found the problem it happens all over again.
While waiting for the “tow truck” my wife says try it again, you know how it acts sometimes.
The car started up, acted fine, and I drove it about 2 miles to his shop and he gave me and my wife a ride home.
I am at a total loss as to what’s going on with this car.
By the way, the digital dash started jumping around but went back to normal before the car started missing and then quit.
Anybody out there have any ideas?
Thanks
Herb
I was cruising along on I-10 when my Vette started missing and backfiring.
I was able to get off at an exit close by.
I called a tow truck and by the time it arrived the car was running fine.
I took it to a shop the local corvette club
Recommended.
They couldn't find any thing wrong.
It left me stranded again a few days later.
Since I have a Delteq ignition I suspected that's what it was but it checked out fine according to the trouble shooting guide.
It got to where it would turn over but would not start.
After playing around and not getting anywhere I called a shop familiar with the ignition about 70 mi away.
I called a tow truck and the driver asked if it would start.
I told him it hadn't started in a month.
I tried it and the damn thing started!!
The shop had it a week and it kept running.
Finally, it started acting up.
They told me they believed it was a security issue.
I told them I never thought of that.
After waiting a couple of weeks for their
Friend at the local Chevy dealer to confirm their suspicion with some electronic devise, he confirmed that suspicion.
They said I needed to get the security deleted from the chip in the ECU.
I informed them that it was an aftermarket chip from Ed Wright.
I had the shop overnight the chip to Ed because he was getting ready to go racing for a week or so.
The shop called and told me the chip was back in the car and they started it many times and drove it around.
They said it was ready and I went to get the Vette. I was happy!
20 mi later I stopped to wash the car. It started and I let It idle when I saw the tach needle jump and then it quit.
It would start, miss & spit, and quit.
I had just spent over $400.00 and I was furious!
I tried calling the shop and could not get anyone.
I ran the battery down trying to get it to stay running. Hello tow truck.
After waiting over an hour for the tow I tried a jump. The car started and ran fine??
I made it to Cruising the Coast, about 80 mi. away. I drove it around that night and parked it.
The next night when I went to leave the Vette started right up.
I made it about a mile down the road and it started doing the same thing as before. Missing,backfiring etc.
I didn't want to leave it so I kept trying to get it going and it finally did and off we went. This happened about 5 or 6 times. Each time I was about to give up when it would run good and off we would go. It always would turn over.
I'm lucky I didn't blow the heads off it was backfiring so bad! I did blow the insides of my CAT’s.
The pieces were hitting my cousins car behind me.
After I finally got it home I then thought maybe it’s my fuel pump and that’s why it backfired because it was running lean.
I changed the pump and the car started and ran fine.
I thought it was “MAYBE” the answer. It wasn’t!
It quit on the way to fill the tank. I had 5 gallons on board.
After checking everything including my injectors I went again to a different president of a Corvette Club.
He told me about a place which was close by where the guy has been working on Vettes for over 40 years.
I didn’t even know about the place!
Oh by the way. I called Ed Wright and asked him what he thought.
When I told him the problems I was still having he told me in his gruff voice “You didn’t tell me it happens while you were driving. The security issue is only when your car will turn over but won’t start!” That’s more money I threw out the window. Who knew?
Anyway, back to the shop that’s been working on Vettes for 40 years.
I had the car towed (again) to his shop.
In a few hours he said it was my Opti Spark.
At this point I had my suspicions that the Opti was a problem.
In about four hours he called and said the rotor was in pieces. I informed him the DelTeq ignition doesn’t need the rotor. He said I know but these pieces would fly around in there and block the light sensor at times. It sounded logical to me.
He called me and said it’s running fine, he drove it around.
I said great!
When I picked the car up I told him if it runs good for more than two days he’s the Man.
He laughed and said that’s a GM Opti, you won’t have anymore problems.
One mile down the road the car quit!! I could not believe it!! Another $400.00 down the tubes.
When I called him he thought I was kidding him. I told him I wish I was.
While waiting for the “tow truck” I tried numerous times to get it started but it would not even try.
As usual it always turned over.
A few days later he called and said it now appears it’s the ECU.
I say ok,do it!
He sent the ECU off to be checked. The company tells him they found some problems and some corrosion and will repair it.
A couple weeks goes by and I call to find out what’s going on. He tells me he just put the ECU on the car and it would not start and the digital dash was jumping all over the place. NO!!
He said he called the place back and they said to send the ECU back.
He calls me back a couple of weeks later and says well, we got the ECU back. The dash isn’t jumping around. The car starts right up but only stays running for about 10 min. then quits. When will this end?
He says he called the company and they are sending him a brand new ECU.
A few weeks later he calls and said the Vette is running great. Eureka! It’s about time.
Another $500.00 bucks and the car is running great!
I drive it for about 6 miles, got on it about 3 or 4 times through the gears, no problems.
I park it in the garage and didn’t get back to it for over a week.
Just before Christmas I tell the wife let’s go for a ride in the Vette. She says you want me to follow you?
I say Nah it’s fine now.
I should have listened to her as usual. The car started acting up just like it did when it all started and then it quit. It will start missing badly. The tach needle will jump and it will spit and back fire if you try to keep it running by playing with the gas pedal.
When it quit, I just pulled over and called the shop.
I could tell by his voice that he didn’t want to see my car again. He said before he called me to tell me the car was ready he drove it for about 50 miles. I told him that doesn’t mean anything. Everytime I think we’ve found the problem it happens all over again.
While waiting for the “tow truck” my wife says try it again, you know how it acts sometimes.
The car started up, acted fine, and I drove it about 2 miles to his shop and he gave me and my wife a ride home.
I am at a total loss as to what’s going on with this car.
By the way, the digital dash started jumping around but went back to normal before the car started missing and then quit.
Anybody out there have any ideas?
Thanks
Herb
01-04-2012, 12:24 PM
#2
Drifting
By now, you know that finding an intermittent problem is more than frustrating. Many of the engine control circuits use very low voltages to operate, and they depend on good, clean grounds. Not sure what year your car is, but I would check all the grounds for clean and tight connections. You will need a good wiring diagram, or the FSM, to find all of them. I'm assuming there are no codes stored, which would point you in some logical direction.
01-04-2012, 12:39 PM
#3
Le Mans Master
Member Since: Jan 2006
Location: Woodstock Georgia
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It sounds like an igntion problem. Missing and backfiring usually are related to timing. So I would suspect the delteq system. A friend on another forum just went thru the same thing, finally found more than one bad coil pack and one bad wire. Sure hope you get it figured out before you go bankrupt.
01-04-2012, 04:00 PM
#4
Drifting
It sounds like an igntion problem. Missing and backfiring usually are related to timing. So I would suspect the delteq system. A friend on another forum just went thru the same thing, finally found more than one bad coil pack and one bad wire. Sure hope you get it figured out before you go bankrupt.
This bears checking out, also.
01-04-2012, 05:20 PM
#6
Melting Slicks
Member Since: Dec 1999
Location: Austin, TX
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Holy moly!
Sorry if I missed this part (I kinda dozed off for a while there
):
Did you ever try running it without the delteq since the problem started? i.e. just with stock ignition?
Even though it checked out according to the troubleshooting guide that doesn't mean it's REALLY working fine. The delteq box could have an intermittant bad connection or something else screwy. That's the first thing I'd try.
Sorry if I missed this part (I kinda dozed off for a while there
):Did you ever try running it without the delteq since the problem started? i.e. just with stock ignition?
Even though it checked out according to the troubleshooting guide that doesn't mean it's REALLY working fine. The delteq box could have an intermittant bad connection or something else screwy. That's the first thing I'd try.
01-04-2012, 07:44 PM
#7
Safety Car
Put it back to stock, and check every ground on the car.
I would NOT be mad at the last guy to do the work. These kinds of problems are VERY hard to find. If he drove it for 50 miles and it did not act up, what else do you want him to do? I would call that above and beyond what he needed to do.
IF you got your dash jumping around weird voltage things are happening. Sounds very intermittent and very electrical in nature. Good Luck.
I would NOT be mad at the last guy to do the work. These kinds of problems are VERY hard to find. If he drove it for 50 miles and it did not act up, what else do you want him to do? I would call that above and beyond what he needed to do.
IF you got your dash jumping around weird voltage things are happening. Sounds very intermittent and very electrical in nature. Good Luck.
01-04-2012, 09:00 PM
#10
Racer
Member Since: Apr 2003
Location: Detroit MI
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Here is where you can get the details http://www.ttspowersystems.com/DataM...ownloads2.html
That is exactly how I diagnosed a hot idle stall.
Datalogged the ECU inputs and waited for it.
In my case the MAF sensor signal was shooting up just as the rpm fell adding fuel that was causing it stall.
It can be alot to taken in all the data and determine what is the offending input is.
Datamaster can also read your codes. You have not mentioned if you have a check engine light or any codes.
01-04-2012, 10:12 PM
#12
Le Mans Master
I suggest that when the problem happens again check for spark and fuel pressure.
This may be going back to square 1, but I think there has been a lot of ground covered already and starting with the basics might be a good idea.
I realize that checking some of these items on the road without the right equipment may be hard to do. But if possible, if it is not running in an controlled location they should be checked.
Checking the electrical and all the suggestions is good advice. Going back to a basic opti is a big step but might fix the problem.
I see that it is a 93 with a ECM. They do cause their fair share of strange problems. They been known to have heat related problems and cooling them off has been a troubleshooting method. Doesn’t sound like the ECM or fuel pressure was ever addressed. Even if fuel does not sound like it is the problem, it would be best to eliminate it and then go in the ignition again direction if need be.
This may be going back to square 1, but I think there has been a lot of ground covered already and starting with the basics might be a good idea.
I realize that checking some of these items on the road without the right equipment may be hard to do. But if possible, if it is not running in an controlled location they should be checked.
Checking the electrical and all the suggestions is good advice. Going back to a basic opti is a big step but might fix the problem.
I see that it is a 93 with a ECM. They do cause their fair share of strange problems. They been known to have heat related problems and cooling them off has been a troubleshooting method. Doesn’t sound like the ECM or fuel pressure was ever addressed. Even if fuel does not sound like it is the problem, it would be best to eliminate it and then go in the ignition again direction if need be.
01-05-2012, 01:10 AM
#13
I read everything up here, and am very interested to see you fix the car... you have gotten some good advice, and some awesome offers of help.....
However, I did want to add, that the performance shop I am affiliated with here in PA, we deal with alot of F-body LT1s.... ALOT. Last year we had two formulas with a similar problem. After doing some of the things you did above and having the same problems, we (for the heck of it) pulled the ICM (Ignition Control Module) off of my car, and put it on one of them. Never had the problem again. When the second one came in with the same problem, we started with that, and resolved the problem as well. Now, Im not familiar with running anything more than just a fully functioning Opti, so excuse my ignorance if the Delteq interferes with my input.
However, I did want to add, that the performance shop I am affiliated with here in PA, we deal with alot of F-body LT1s.... ALOT. Last year we had two formulas with a similar problem. After doing some of the things you did above and having the same problems, we (for the heck of it) pulled the ICM (Ignition Control Module) off of my car, and put it on one of them. Never had the problem again. When the second one came in with the same problem, we started with that, and resolved the problem as well. Now, Im not familiar with running anything more than just a fully functioning Opti, so excuse my ignorance if the Delteq interferes with my input.
01-05-2012, 10:44 AM
#14
Racer
Thread Starter
Holy moly!
Sorry if I missed this part (I kinda dozed off for a while there ):
Did you ever try running it without the delteq since the problem started? i.e. just with stock ignition?
Even though it checked out according to the troubleshooting guide that doesn't mean it's REALLY working fine. The delteq box could have an intermittant bad connection or something else screwy. That's the first thing I'd try.
Sorry if I missed this part (I kinda dozed off for a while there
):Did you ever try running it without the delteq since the problem started? i.e. just with stock ignition?
Even though it checked out according to the troubleshooting guide that doesn't mean it's REALLY working fine. The delteq box could have an intermittant bad connection or something else screwy. That's the first thing I'd try.
I just hate to spend more money without being sure that's the problem.
01-05-2012, 10:49 AM
#16
Le Mans Master
I read everything up here, and am very interested to see you fix the car... you have gotten some good advice, and some awesome offers of help.....
However, I did want to add, that the performance shop I am affiliated with here in PA, we deal with alot of F-body LT1s.... ALOT. Last year we had two formulas with a similar problem. After doing some of the things you did above and having the same problems, we (for the heck of it) pulled the ICM (Ignition Control Module) off of my car, and put it on one of them. Never had the problem again. When the second one came in with the same problem, we started with that, and resolved the problem as well. Now, Im not familiar with running anything more than just a fully functioning Opti, so excuse my ignorance if the Delteq interferes with my input.
However, I did want to add, that the performance shop I am affiliated with here in PA, we deal with alot of F-body LT1s.... ALOT. Last year we had two formulas with a similar problem. After doing some of the things you did above and having the same problems, we (for the heck of it) pulled the ICM (Ignition Control Module) off of my car, and put it on one of them. Never had the problem again. When the second one came in with the same problem, we started with that, and resolved the problem as well. Now, Im not familiar with running anything more than just a fully functioning Opti, so excuse my ignorance if the Delteq interferes with my input.
But I believe the Delteq system does not utilizes the ICM in their usage of complements. I believe it and the coil are not used.
01-05-2012, 11:36 AM
#17
I'd go back to the stock ign and see how it does. That eliminates the aftermarket stuff that is most often behind the problems.
beyond that, go thru ALL the power source connections and grounds. These things get their data and instructions from very low amperage signals and low voltage and something as simple as a dirty connection (not shiney clean) can cause exactly what you ar seeing. I've been there, done that.
beyond that, go thru ALL the power source connections and grounds. These things get their data and instructions from very low amperage signals and low voltage and something as simple as a dirty connection (not shiney clean) can cause exactly what you ar seeing. I've been there, done that.
01-05-2012, 12:57 PM
#18
Pro
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I also agree that going back to stock makes the most sense along with checking all the grounds. the biggest plus is that if you still have the stock stuff, then it is only a couple of shop hours
01-05-2012, 01:44 PM
#20
Instructor
If I have followed your thread correctly the problem looks to me like and electrical open created by heat. I would move returning to stock to Plan B. Plan A would start with the ICM. because of their mounting position they are subject to heat break down. Then I would carefully examine the Weather pack connections on the top of the engine. Along with that effort I would carefully examine the wiring harnesses on the engine looking for heat or burn damage and pull slightly on sections of individual wires looking for a break without an insulation break. Buy a $20 Leslie Tools high voltage tester. Its a glass enclosure with an arc separation. Works great for testing spark plug wires and can be inserted in the Hi-Voltage coil connections (the same on your Delteq). With engine running, start moving wires and Weather Pack connectors. If it is a ground it is probably close to max engine heat or toward the back of the engine around the headers. If you can't identify your failure with engine at operating temp, then disregard this posting. A good tool on this kind of problem if it is heat related is a Remote Reading Pyrometer. They are available from Sears Tools or Harbor Freight for less than $50. A great tool for chasing hot electronics.