y2kfrct

Hey guys, I have a 2000 corvette frc. car has been driving great since the day i owned in, then suddenly yesterday I got "service active handling engine power reduced." The car accelerates dangerously slow, and is hard to get over 50 mph. Also it shakes and does not drive normally. If i turn the car off and wait and turn it back on, it will be normal for a short period of time them then it will start acting up again.

Reaseachring online I realized it had to do with the throttle body. I tried cleaning the throttle body, cleared code and took it for a 20 mile spin, no issues. Then took it to work and back to where it was. It even shut off on the way!

Please help. Any ideas? new throttle body, or new throttle body sensor?

1986coupe

Throttle position sensor. Replace it.

y2kfrct

Is there any trouble shooting that I should do first, or just go ahead and swap that part?

y2kfrct

Is there any trouble shooting that I should do first, or just go ahead and swap that part?

y2kfrct

Now its also code p1515 in addition.
I will swap the throttle body potion sensor tomorrow, hope it works.

y2kfrct

Thanks for all the help man. I went ahead and picked up the tps and will replace it tomorrow morning and see if the problem will go.

thanks again

y2kfrct

Checked the tps wiring etc, all seemed great. Took off the intake throttle body and really cleaned it out well, same issue.

Then after 3 trips to autozone i got the right TPS (they are not the brighest). Put in the tps, put all back together, cleared the code and drove it for 20 miles.

Did open throttle runs, braked in gear, etc trying to set all the codes. Let the car ideal for a few minutes. Came back checked, and those codes are yet to appear

Lets keep our fingers crossed but I think it was the TPS. Will drive some more and see if it acts up.

Thanks for all the help guys, youve been great.

**One last thing, the car has long tubes etc, and previous owner took out the secondary air system so I want to get the car tuned to tune out the codes? Any tuners you guys reccomend and any tuners to stay away from?
For all my stangs I want to dave guy, Wanted to see if there was any shop recommended for vettes within 4 hours of Northern VA.

Thanks!

r.hillenbrand

Where you at in N VA there is a tuner in Frederick Md.

y2kfrct

Whats the name of the tuner? Im in Sterling VA.

There plenty of tuners closer to dave guy, but im looking for a shop that knows what the are doing and price fairly.

If you recommend the tuner what is there contact information and shop name?
Thanks

y2kfrct

So it went all good for a week, today i got on it and bit and 10 minutes later the problem started again. "Reduced engine power, service active management system"

So tps sensor was not it? Could this possible be related to needing a tune up?

I scheduled to tune the car Monday and now this happened. Want to have it fixed before then. Any ideas?
Thanks!

cdkcorvette7

Are you still getting the same codes? Any new ones? With your engine off can you move your throttle body blade easily with your finger and does it move smoothly without binding, When you let it go does it flop back to nearly closed position?

y2kfrct

Hey guys,
Last weekend before replacing the TPS I removed the throttle body cleaned it very well and the blade moved just fine. Codes are just about the same, as stated in earlier posts.

Codes:
P1221
P1515
P0304 (New one)

I have codes P0410 from the secondary air system removed by previous owner. I am getting this code tuned out. My emmision expires in a few days so I need to get above codes taken care of, and the problem resolved before going to the dyno.

Could P0304 misfire be the cause of all of this? I purchased all new wires and plugs that I will swap out this weekend. I did notice that the plug wires run very close to the long tubes, so I will be wraping them in hear resistence tape.
Any imput would be great since I NEED to get through emmisions.
Thanks

y2kfrct

any ideas guys?
thanks

cdkcorvette7

P0304 is a missfire on cylinder four. Check that wire for damage and ensure it is seated properly then pull that plug and take a look at it.

That should not cause your other codes.

Based on the series of events so far I'd almost suspect you got a faulty TPS...

y2kfrct

Hey,
I did a full tune up wires and plugs, and the car runs perfect now deff took care of the misfire in cylinder 4.

Now as to 1221 and 1515 these codes used to cause "reduced engine power" almost everytime I started the car. So i replaced the tps. over 1k miles no issues. It just gave the reduced engine power again and the codes.

Could the tps from the auto part store be bad? The reason im suspecting this is because it works fine 95 percent of the time.

cdkcorvette7

Disconnect it and inspect both the male and female ends of the connection. Clean if necessary then reinstall. Make sure it's seated properly.

y2kfrct

Ok, so today I finally got a chance to drive it and see what codes it would set. over 60 miles no problems ran solid.
only code was p0430, which i will have my tuner tune out, car is catless with long tubes, and p0410 from the secondary air system being removed. both of these im going to have tuned out.

so 60 miles no codes i didnt expect. then i let the car ideal for 10 minutes with ac on. i felt very very light ideal surge. ran codes and p0304 showed up. I already did new plug and wires. checked all is tight and seated properly.
The car runs PERFECT when under load, but when idealing for 5 or 10 minutes the check engine light flashes. So the misfire is only at ideal. any ideas would help. Going to have my friend use a chevy diagnostic tool. The ls1 runs to darn good for something internally to be wrong.
Thanks

MyTVette

I just had the same issue on the way to work this morning. I read this thread but was not clear if the TPS fixed the problem for good or did the problem continue? I'll be checking the throttle body and wiring this weekend and post findings.

I drove the car back home and took another to work. I checked the codes before I started it and got a P1221 TP Sensor 1, 2 Performance read out. I started the car and it seemed to run fine. Thunderstorm looming so I did not drive it. Didn't want to get stuck in the rain.

Anybody have suggestions (other than keeping an umbrella handy)?

MyTVette

OK, I received the TPS sensor from Rock Auto.. Went to remove the attaching bolts and found a unique star pattern with a post in the center and smooth round exterior. Any ideas on where I can get the removal tool? The replacement did not come with new bolts so I'd like to avoid destroying them if possible.

MyTVette

Any help? Thanks in advance.