I recently posted my problem with the Check Engine Light. I got a code 33. So I changed both burn-off & power relays and still got the code 33. So I replaced the MAF sensor with a rebuilt unit (with a 1 year warranty). Now I get a code 36 which is a problem with the MAF burn-off circuit. So I replaced the relays again, disconnected the battery to erase codes and happily drove away. After about 15 minutes driving in the city the Check Engine Light came on again. When I got home I switched the engine off and got my trusty old bent paper clip to read the codes. Code 36 again. Removed the relays, cleaned the contacts and put in the old relays back on again. (The old relays are only two years old) Erased the codes and started the engine and let it idle for about 30 minutes with an occasional "blip" to the gas pedal. No Check Engine Light this time but have not got the time to take it out to give it a good run. OK, what do I check if I get code 36 again? Some manuals state that there is a burn-off module under the passenger's side hush panel, near the ECM. Is this true? Can it be the culprit? How do I test it before I go out and buy a new one? It bugs me to buy parts just to check out if the ones in the car are OK. Plus, I don't have another C4 to change parts with to see what is wrong with the ones in my car. DAMN SENSORS
Anybody knows where I can get a C4 (1987) shop manual? I even tried eBay with no results.

:smash:

 

For the sop manual try Bob Johnson's Auto Literature. They have a web site which should list availability. Be prepared, as these manuals are expensive! You should be able to get a new one from Helm, Inc. and I believe The Last Detail may also have them.

 

Try this...
http://www.helminc.com/helm/product2...2N1MSDD1J307G5

 

My '87 shop manual does not show a separate burn off module on the wiring schematic. It does say "a burn-off signal to the MAF sensor,while running, may result in a Code 33. Be sure relay connections are clean and check CKT 994 for a potential short to voltage". CKT 994 is the DK BLU wire from the MAF sensor to both the burn-off relay and the power relay. It shows the DK BLU wire on pin E on the burn-off relay and pin C on the power relay.

 

:cuss This is an update of the problem. On Sunday morning, before going to church, I disconnected the battery for about 30 minutes (I read somewhere that a few seconds is not enough), reconnected it and drove the car to church. SES light did not light up. While driving, tried to catch a Porsche Boxster that passed me doing about 90 MPH so I hammered it WOT. Car responded fine and hit 110 MPH before my turn off. After church, I started the engine and the SES light lighted up. I noticed the idle (600-700 rpm's) was rough and the engine was missing intermitently and surging slightly. So I drove home and hit it WOT in a nice piece of road until I hit 98 mph. It did not miss. When I stopped at a red light, the idle was terrible and the engine started to miss during acceleration. It felt like one or two spark plug wires were loose. When I got home I checked the wires and all 8 were in place and tight. The exhaust smelled like raw unburnt fuel. Checked the codes and pulled a code 36 again. No other codes. What can be happening here? New relays and MAF sensor and now it is worse. Any ideas? :mad
Note: I did not catch the Porsche :rant: it turned off before I could.


[Modified by alfonso gomez, 1:21 AM 10/13/2003]

 

Thanks. Will buy it next week. :thumbs: