goldeneye_vet

Surging, hunting for idle and running poorly while in my driveway at operating temp. I have used an AutoXray 5000 however I don't get any codes. If I use my high dollar paper clip tester I get code 33. Using my helms trouble shooting list it says to check the burn off module in the dash for high temp code 33. What are the symptoms of your MAF going out? I have removed the screens and the fins from the MAF and do use a K&N filter. I did spray the module with carb cleaner this morning in a vein attempt that this possilby was my problem. Note that the mods to my MAF were done 2 summers ago and has been running fine ever since until yesterday. All seems well in appearance with the MAF but I'm stumped. Any ideas or do I just replace the MAF? It throws me off a little when my scanner does not pick up codes. Do these go bad over time or does it happen all of the sudden like this one did? Thanks for any help you can give!!!!

jimcork1

It's been a while since I had my 87 but if I remember correctly I thought 33 was O2 sensor. Replacement of the O2 sensors correct my stalling problem. 99 Nassau Blue

jackdaroofer

IMHO code 33 is definitely MAF and more than likely relays, but since you neutered the MAF, and sparayed it with fluid, I cn't be positive.

First, without too much testing, replace both MAF relays, the power and the burn off, clear the codes and see if you still have the problem. You have to replace both relays( don't ask why )

This is a cheap approach! both relays should cost less than $ 30 and if the solve the problem, you got away cheap

If it turns out to be the MAF itself, you still needed to replce both relays with the new MAF so you haven'y wasted money

One othe place to check, spray alcohol into connection at MAF sensor to clean it up. if it gets grungy it can give you problems

seeya

jackdaroofer

IMHO code 33 is definitely MAF and more than likely relays, but since you neutered the MAF, and sprayed it with fluid, I can't be positive.

First, without too much testing, replace both MAF relays, the power and the burn off, clear the codes and see if you still have the problem. You have to replace both relays( don't ask why )

This is a cheap approach! both relays should cost less than $ 30 and if they solve the problem, you got away cheap

If it turns out to be the MAF itself, you still needed to replce both relays with the new MAF so you haven't wasted money

One othe place to check, spray alcohol into connection at MAF sensor to clean it up. if it gets grungy it can give you problems

seeya

goldeneye_vet

Unfortuneately 85's have a burn off module that is located behind the bread box in the cabin of the car. These modules are SPENDY!!!!! I have cleaned the connectors both on the MAF and the pigtail to the MAF with no luck. I don't think the autoXray 5000 is able to process the data from this slow computer too well. In the observation mode the idle goes to 1000 rpm's which is ok as its running great just a faster idle but it doesn't look like its giving me any other trouble other than the MAF. I'm at my wits end on this one?????? HELP???? Or should I say Calgon take me away!!!!!!! PS..........I should point out a few things that I did gather from the scanner. The oxygen sensor (3 wire sensor as I have headers) is reading 572 mvolts. My MAF sensor is reading at 9 grams of air per second. This increase's steadily as I increase the rpm's. The car is in closed loop as well according to the scanner.

vader86

I wish people would pay attention and realize that 85 doesnt have the 2 relays. Only one behind the breadbox.

The screens and fins doesnt affect the testing or anything, disconnect it and see if it runs better or you can usually tap it with a screwdriver and if that affects anything. If it does its the MAF.

goldeneye_vet

Tried the tapping with a screwdriver and disconnecting and that didn't work either. The only other thing I can think of is that I have no smog equipment from the pump to the diverter valves. I had the wires for the diverter valve and check valve taped together nicely and stuffed close to the TB and it had been that way since I removed all of the equip last summer. Yesterday I moved that harness out of the way to see what was needed to do the TB bypass and failed to put the harness back into its comfy home. I shut the hood, dusted my ride off and went to the auto parts store to get what was needed. Along the way that harness got removed by my pulley's. Sitting at a stop light and all of a sudden the car starts running rough and searching for idle. I got her home, let it cool off and started tracing wires to see what else it could be from that harness and see nothing abnormal other than 5 ripped wires dangling there. 2 black, 1 brown, and 2 pink. Don't quote me on the color but its close. I took those wires today, taped them up, and put them away and still have the same problem. I've traced them back to as far as the injector harnesses on the driver's side. No cuts or pulls in the wire at all. I wouldn't think that those wires being ripped and all would have any affect on the car. That's all I can come up with. Bonehead move on my part but I don't think they have anything to do with my code 33. Am I wrong? Thanks for the input so far!

Aggravated4life

Did your MAF wires/connector wires get touched? I think theres a Green wire that handles the code 33 if theres a problem.It should be the last wire on the passenger side of the connector If I rem.correctly.Make sure those wires are good and the connector isnt loose or broken.

Because you posted the wires got hit,I cant help but wonder maybe there is a problem with the harness somewhere.

Alos,what is your TPS reading? A bad TPS reading will set a code 33 and make the car run rough as well.This happens alot when installing a larger TB and installing the TPS but its out of whack due to the different range of the new TB and etc.This may happen with wires that got cut or chewed.Not sure but just throwing ideas what may help.

Aggravated4life

One other thing,lets say the pulleys caused the problem hitting your wires.You taped them up and theyre fine.Did you disconnect the negative on the battery to clear the code?If not,it will remain until you do,even if you made a repair.You can try that as well.If you get a code 33 and the car runs rough,then theres more work to be done.if its just a light,it could be the code is left over from before.Does the light stay on all the time or just lights up a few minutes later?

goldeneye_vet

I've disconnected the battery several times after each reading with my scanner and my trusty paper clip to get a good read on the problem. The harness to the MAF is solid with no nicks or cuts. Seems to be in good shape. Using my test meter I get milivolt signals from the wires and get good ground from the two wires that are ground on that harness. My TPS reading according to my scanner is .054 volts at idle and moves accordingly with the throttle. One last peice of info that I should add is that the AutoXray 5000 picks up 3 other codes that I don't get with my paperclip. Code 52, 53, 54. Too much voltage, calpak missing, fuel pump relay. This is the reason I don't think my brother's $400 scanner is working the best or I attribute them to the poor running condition that the car is in right now. Remember the car is searching for idle and running rough. I think this is all of the info I have left that I'm aware of. Maybe in the morning before I go get my new MAF I'll look further into that harness as that is the last thing that I can think of. Or better yet somebody has a magic wand and it will be fixed in the morning. I love this car!!!!!!!!!!!!!!!!

goldeneye_vet

I just found a nice little article from www.corvettefever.com that gives a good rundown of things to look for on code's 33 and 34. It mentions in my case that it might be best to run new wires back to the burnoff module and ecm in order to fix the problem. Just a nice weekend project. Thanks for the reply's to my problem!!!!

Morley

Since the harness got yoinked by the pulleys, remove the connector from the MAF and have a look at the pins in it (female) make sure none of them got spread open. Next look at the pins on the sensor and make sure none of them got bent either.

goldeneye_vet

Tried that too Morley. What I didn't check was voltage to those wires with the vehicle running. I'm not sure if there is a difference when the key is in for diagnostic mode and the voltage that goes to the maf bundle of wires when the vehicle is running or not. I'll try here next and go from there. All things considered if I didn't have to buy a MAF sensor that would be great. I have one lined up and ready to be picked up this afternoon but I'm going to forego sleep this am and do some more testing to make sure that this is what I need. I'm fortuneate enough to work the overnight shift so this should be a big help. What I should have done is spend more time with my helms and following the diagnostic trails but I got scattered brained and tried to do all this at once and this problem is going to take a little more patience. I don't know why I'm so optimistic but it will work itself out. Thanks to everyone for all the help so far. Having a helms is a great tool but I must confess I expected more from my manual than a stack of reemed paper that gets delivered in a box. This rant is for another time though.