88 Cutlass Calais 2.3 L (Quad 4) Please help!!

[tetrabetta2001]

This one is a long one, sorry, just want to give all the info I can. Thanks. :-)

I am having issues with my car. The car runs rough at idle, surging, sputtering, sometimes kinda sounds like misfiring (could be wrong), also I think my fuel/air ratio is too rich cause I hear popping sounds coming from my exhaust. Runs bad at cruise aswell. Lack of power sluggish, sometimes surging. If I floor it however, it runs just fine, as if nothing is wrong with the car. I also seem to be going through a lot of gas. I am getting like 7 miles to the gallon, when I usually get between 20 and 25. I have replaced the MAP sensor, TPS sensor, air filter, fuel filter, and did an oil change. I dropped some fuel system cleaner in the tank to no prevail. I took it to two seperate shops. One shop was a rip off, however, the other shop had only ASE master technitions and they said they thought it might be the fuel injectors.

The first shop said it could be my timing chain or FI wiring harness. I replaced the wiring harness from one at a junkyard (tested it to make sure it was good first), still ran like crap. Checked the timing chain and sprockets, looks brand new. I did however, have a bad timing chain tensioner with cause my chain to slip after I got it all installed, bent my intake valves on cylinder one. Replaced the valves and timing chain tensioner. Has not slipped again. The timing chain makes noise in the housing, however I thought I read a service bulletin that stated that the noise from the timing chain housing was normal. They replaced my spark plugs (without my authorization) one I found out later was bad, replaced it at half the cost.

The second shop at first thought it was the ECM, however, on further tests they concluded it was functioning normally. They then told me my FI were bad, however, after doing my own little test (unplugging the FI one by one to see if it affects the engine) I found all of them affected the engine when I pulled their plug. Leads me to believe that is not the problem. (am hoping I am right those things cost $150 a piece)

I once heard if you pull the vacuum line on a fuel pressure regulator that it will cause the engine to run bad, I did pull the vacuum line and it didn't change the way the engine ran. However, that is a $100 part, would like to get some opinions on that before I buy it.

I am at a loss not sure what to do. Please someone if you have any ideas, I am all ears. Thank you. :-)

[tetrabetta2001]

I guess everyone else is as stumped as me, lol. Thanks to all those that looked. :-)

[Rockett30]

I had a similar problem with my 88 Calais 2.3 Quad 4. I was coming off the freeway one day and all the sudden it started running like crap. Idled very rough and sputtered and all. I got home and left the engine running and used a long screwdriver to listen to the injectors (put tip of screwdriver to injector and then put ear to screwdriver). I discovered that 2 of the injectors weren’t firing correctly (2 clicking fast and 2 clicking slow) I removed the plugs to check them out and found that two of them were wet. I pulled off the fuel rail and had my wife turn the key to the run position and the injectors for cylinders 2 and 3 started spraying a bunch of fuel. Turned out that my ECM was faulty even though there were no error codes. Bought a new ECM from Advanced Auto (www.partsamerica.com) for $100. Car runs like a champ now.