1996 Pontiac Sunfire

Tiny
SCOTT MACCONNELL
  • MEMBER
  • 1996 PONTIAC SUNFIRE
  • 4 CYL
  • 2WD
  • MANUAL
  • 205,000 MILES
This is a on going problem I have had it two a few diffreent people and the problem is that the car starts and runs relly rich. I have no codes and a list of parts that I have changed some made run a little better but not fixing the problem. We started with the map sensor, then went two the computer, the coolent temp, timing chain, injectors, all along I have been putting in new plugs 3 or 4 sets they all come out right black. The only way too start the car is to put the pedal to the floor then is starts but runs with a miss. The scaner has been of no help the car can run with it hooked up and all of the reading are in range or close but it will not even show wich cylinder is missing and keep count, it shows cylinder 2, 3 have slite miss but it will not stay on the screen or keep count of the miss. I dont know what else to do but it is starting to get very costly and not shure if I should put more money into it or not. All if the parts that I have replaced where worn but still working, the timing chain was streched out, the injectors had a small drip, map and temp read ok on scaner but tryed in hope that it would fix the problem
Do you
have the same problem?
Yes
No
Monday, January 14th, 2008 AT 9:49 AM

4 Replies

Tiny
MASTERTECHTIM
  • MEMBER
What is your exact size engine. There are some quad 4 engines that have a problem with the oil pressure relief valve sticking causing high oil pressure. Ive seen this problem a number of times. When the oil pressure is high it puts too much pressure on the lifters causing them not to release, which then holds the valves open causing low compression. You can check this by checking the compression when this happens. After it warms up the problem goes away. Let us know how you make out.
Was this
answer
helpful?
Yes
No
Monday, January 14th, 2008 AT 12:01 PM
Tiny
SCOTT MACCONNELL
  • MEMBER
I have a 2.4 l and did a compression test and had lots of compression. I had some one tell me about oil pressure I dont think that that is the problem the oil filter is still in the shape it came not biger or swellen. I am also not shue how to tell if the timing is set right can you tell with out taking the cover off and looking at the gears. I did the timing chain my self and I am 99% shure that the timing is right but I do have that 1 % that it could be not right.
Was this
answer
helpful?
Yes
No
Monday, January 14th, 2008 AT 12:21 PM
Tiny
MASTERTECHTIM
  • MEMBER
The 2.4 is the engine with the oil pressure problem. Does it seem to crank real fast when this happens, that is another way to tell if its the oil pressure problem. The engine will turn over real fast. Also another thing ive seen cause this is the ecm ground on the transmission bell housing stud. Its either brown or black wire, where the grounds are at the bell housing studs, lightly tug on wire to make sure the wire is not broken inside the insulation. This will also cause the rich condition.
Was this
answer
helpful?
Yes
No
Monday, January 14th, 2008 AT 12:46 PM
Tiny
SCOTT MACCONNELL
  • MEMBER
In my search I have also found out that there is a recall on the fuel pumps for the sunfire this is a problem because I did replace the fuel pump on the car but it was out of a parts car and I dont have the car so I cant check the vin # to find out if I have one of the bad pumps it almost sounds like that could be the problem. Is there a way that I can check the pump? The recall was because the pump return line and the mars vent line got put in wrong spot.
Was this
answer
helpful?
Yes
No
Monday, January 14th, 2008 AT 2:22 PM

Please login or register to post a reply.

Recommended Guides