I have a 1987 Camaro Iroc with the 5.7. It has just started idleing rough and now has a hesitation. Once you start moving the engine is still strong no knocks or noises. Also the check engine light has come on. I am hoping some of ya'll have had this problem and may know what to look for. Thanks Keith

Sounds like an oxygen sensor, but on puter cars who knows? My '87 acted up back in the summer and I got all kinds of potential solutions from the nice folks on this site. TY to all. My prob turned out to be the IAC valve. My advice (for what it's worth) is to thoroughly clean the throttle body butterflies first and eliminate that, then get a dealership mechanic to run the codes on a hand-held diagnostic box if they still have one for an '87. If no codes show up, Lord help you. It's a turkey shoot. I got lucky.

I *think* on the 3rd-gen ECMs you can short two pins on the diagnostic connector, turn the ignition on and count check-engine light flashes to get the codes. But I'm not sure which terminals, so I'll let another member verify my facts.

I recommend getting the codes first and then troubleshooting the problem from there. What's more, those earlier ECMs would tend to trip all sorts of codes for a simple issue. So you've got to take all the codes, and apply some deductive reasoning to figure out what the problem may be. For example, the ECM may say the O2 sensor is too lean, but the root cause may be a vacuum leak instead of an expensive O2 sensor.

its pin a and b. top row...last two on the right side. connect the two with a piece of wire then put your key in and turn it but don't start the car. the check engine light will flash 12 if you've done it correctly. then it'll flash all the fail codes 3 times each. goodluck

usmc,

You are correct. It's the A & B terminals. I used to do this on my 1984 Z28. You can do it with a paper clip. Just bend it so it gets in the A & B terminals at the same time. Then follow usmc's directions.

Good Luck!!

I have a 1987 Camaro Iroc with the 5.7. It has just started idleing rough and now has a hesitation. Once you start moving the engine is still strong no knocks or noises. Also the check engine light has come on. I am hoping some of ya'll have had this problem and may know what to look for. Thanks Keith
Take brightblues advice and have your OBD1 scanned by a dealer tech.The dinosaur Tech 1 is still floating around and has can read parameters.The DTC is a referance,any good dealer wrench just builds off that.We have corner shops sending us their nightmares all the time.We bill them and then they call you all fixed with a 10% mark up.Funny thing,we usually see $500 worth of sensors thrown at it to start.I can not vouch for every Chevy store or tech but I do know GM demands across the board factory training and ASE certs from its dealers.Back to your question.The check engine light is your ecm,s way of alerting you to issues,but the stored code can be just a byproduct.For example.A low fuel pressure issue can induce an 02 code.Do we automatically replace the 02 sensor or monitor fuel pressure???.You decide.