1988 camaro check engine light

[acalwell]

i have a 1988 camaro and the check engine light comes on and i took it to auto zone and they said it as code 33 or 34 or 35 which they said could be the mass airflow sensor or egr valve or control module ignation. how can i tell which one it is. thanks april

[Morley]

Which was it 33, 34 or 35? Each code has a specific meaning.
Tell ya what. Do this... Take a paperclip and straighten it out, then bend it in a narrow U. Now locate the ALDL. It is under the dash by your right knee. It should have a 1" X 2.5" black cover over it. Next take the paperclip and stick the ends in the top 2 right hand most pins (pins A & B). Now, turn the key on but do not start the car. The fan will kick on and there will be some clicking under the hood...all normal.
Now, watch the check engine light..it will begin to flash. it will be "flash" < pause> "flash, flash". This is code 12, it means that the ECM is ready to communicate. It will flash code 12 three times then start flashing out the stored codes. Example... "flash, flash, flash" <pause> "flash, flash, flash, flash". This would be code 34. It will flash each stored code 3 times until it has run through them all and then it will start all over again beginning with code 12. Now you can turn the key off and remove the paper clip.
Come back here and post what codes you got. DO NOT go out and start buying parts. A MAF is $500, and even if you have a MAF related code it may not the the sensor itself that is bad. There is a whole lot of troubleshooting to do before you replace parts.

[acalwell]

ok i did that and mine will flash flash flash pause flash flash flash and than it will do that 3 times and than flash flash flash pause flash flash and repeat code and than flash flash flash pause flash flash flash flash and repeat that three times than starts over with the first code. the car runs good just hard to start and ildes low when you stop. does that mean i have 3 things that could be wrong since it gives 3 codes?

[acalwell]

oh yeah and is it true if you take a screw driver and tap the mass air flow sensor and the car shuts off its bad. because the guy a auto zone told me that and i tried that and my car didnt shut off when i tapped it with a screw drive. thanks april

[acalwell]

ok i did that and it is flash flash flash pause flash flash flash and it will do that 3 times and than flash flash flash pause flash flash and does that code 3 time than flash flash flash pause flash flash flash flash 3 times than starts over with the first code again. the car runs good but its hard to start and when the temp gets up to 220 thats when the check engine light comes on. and will idles low when you stop. i dont know if its true but the guy at autozone told me if you take a screw driver and tap the mass air flow sensor with the car running and the engine stops its bad. so i tried that and it didnt die when i was tapping it with a screwdriver. so with 3 different codes does that mean there are 3 things wrong? thanks april

[Morley]

You have a code 23 a 33 and a 34
For the codes 33 & 34 replace the MAF power relay AND the MAF burn off realy (they cost about $20 each). They are located by the brake booster along with the fuel pump relay.
The code 32 is for EGR, which, if it is stuck open would explain the low idle.
First replace the relays, disconnect the battery for a few minutes. Then reconnect the battery and drive the car and see if the codes return.
If the code 32 returns, don't sweat it, we'll tackle that one once the MAF codes are done.

[acalwell]

i called autozone to get a maf burn off relay and maf power relay but the guy told me all they have a is mass airflow sensor so he said that was probly what i needed. is that right? thanks april

[acalwell]

can i just buy 2 mass air flow sensor relay and use one of them for the burn off relay? because the auto part store has no ideal what iam talking about lol. sorry for asking dumb question but i am a female and i understand what parts you are talking about but the auto part store confuses me because they said they have never heard of a maf burn off relay. so now iam confused. but i will buy the mass airflo sensor relay tommorow. so as wondering if i needed to buy 2 and use 1 for the burn off relay. thanks april

[acalwell]

ok i think i found what you are talking about if you can tell me if iam right and these are the parts.http://cgi.ebay.com/ebaymotors/_Car-...4506.m20.l1116

[acalwell]

and if this is the maf power relay http://www.autozone.com/N,15901319/s...eResultSet.htm

[Morley]

Your second link was a dead end, it was for a 1995 Camaro.

BUT, YES! The burn off and power relays are the same part number.
This is what you need http://www.autozone.com/N,15901319//...eResultSet.htm
You need 2 of them.

DO NOT buy a MAF sensor, we aren't to that part yet. Code 33 is 99% of the time is from a bad power relay.

[acalwell]

i got the parts today ok is one located up towards the front of the car by the battery and radator? i found the one mounted on the back wall of the car by the fuel pump relay but didnt see one there with the same number on it but found one that look just like it with the part # being the same up by the front of the car is that the 2 i change? thanks very much april

[acalwell]

ok i got the maf sensor relays on and now the only code it reads is 32 for the egr valve. thanks april

[Morley]

Originally Posted by acalwell

ok i got the maf sensor relays on and now the only code it reads is 32 for the egr valve. thanks april

Weeeeee! Ok, first problem solved.
Now. Look under your plenum and find the the EGR valve. It is aft of center and has a flat metal "can" on top of it. On the front of the metal body (bolted to the manifold) there should be a wire coming out of it that then heads to the back of the engine. This is the diagnostic switch. Make sure the wire is hooked up at the EGR. Then follow it back to where it goes behind the engine. Gently pull up on the wire until the connector can be seen, Make sure the connector is hooked up.
Next, get a mirror, Walmart sells an inspection mirror and magnet set for a couple bucks. Take the mirror and put it under the EGR valve diaphram housing (the flat metal can) and look at the under side between the "spokes". (use a flashlight if you can't see). Have someone start the car while you watch the diaphram. It should NOT move upwards. If it does, the valve is stuck open or the solenoid is shorted and needs to be replaced. If it remains closed, rev the engine a little and watch for it to open, it shouldn't. If that is goodm, shut off the car and get a hand vacuum pump (like mity vac) and hook it to the nipple on the diaphram housing. Slowly operate the pump to apply vacuum and watch the diaphram, it should open. If it won't open, change the valve. If it opens, get it all the way open and pinch off the hose, it should stay open, if it doesn't stay open, replace the valve. If it does stay open then the diagnostic switch is either bad or the solenoid is not operating. The easiest part to get to is the solenoid. It should be mounted to a bracket on the RH side of the intake manifold towards the rear (the hose that was on the EGR goes to a rubber 3 way joiner that hooks to the solenoid). If the solenoid doesn't fix it, you'll need to remove the plenum to get at the diagnostic switch.
EGR isn't "essential" for the engine to run (if it isn't stuck open) but it does help control detonation and that light can be bothersome.

[acalwell]

ok i will try that this weekend. after i changed the maf sensor relays its still hard to start does that have anything to do with the egr valve? thanks april