Hello Group!

I bought a used 89 Trooper a a couple years ago which had 200K miles on it. A few months after buying it my check engine light came on and maybe a year after that or so my O2 sensor light came on. I was able to resent the check engine light by taking the instrument panel apart and then I tried to get it smogged after an oil change. Well, the mechanics laughed at me since my idle was so rough and the engine was running so poorly. They recommend I get a tune-up as not to waste time and money.

So I changed the spark plugs and the rotor - I clean out the cap and used the old cap. It made an instant difference and the engine runs smoothly - it doesn't seem to want to jump out of the engine mounts at idle anymore.

I thought I was getting closer to having things fixed but then the check engine light came on again. The O2 sensor stayed off though.

I cannot pull the codes for this car. I see the wires that I'm suppose to connect but nothing happens when I connect them. I connect them with the engine off, then I turn on the electical with the ignition switch but nothing.

Weird syptoms: my car will not startwith out giving it a lot of gas and I'm the only one who knows exactly how to do this. It takes a real specific foot! I have to "trick" the engine into starting... If I don't the engine will start for a couple seconds and then die.

So of course there is a major issue here. I tried cleaning my MAF. I've given it a "tap" test and I have put it on the multi-meter and it seems good in terms of increasing and decreasing voltage readings with respect to my throttle.

One interesting thing about my MAF is when I unplug it while the car is running it immediately dies. I have read that the ecm should take over.

So I think my MAF is good. Even though my O2 sensor light stay on I replaced it and it seems to make my car run stronger. But, I'm guessing it didn't do that much overall.

Point #2. When I changed my rotor I found oil in my cap. I had a leak in my rotor shaft seal. This is also where the Crank Position Sensor is located. It made sense that with a shorted out CPS my car would not start correctly and run roughly. I pulled the shaft out through a new o-ring on it - the old one was worn flat. I cleaned up my CPS and put it on the multi-meter. I spun the little metal disk through the sensor and I would get readings alternating between 5V and 15V on my cheap multimeter. They were consistent though and the CPS seemed to be doing it's job of sending those signals to the ECM.



Point 3# I did try to clean out my throttle body. After I did this the car only idled very high - very annoying. Since then the idle has come down.

Sometimes when I pull to a stop the idle will go up and down up and down and I'm thinking, someone just shoot me please.

Usually when I accelrate and the engine feels "strong" the engine light stays off. When I decelerate it will come on. If I shift gears too early and bog the engine down a bit the engine light will come on too.


I've missed my registration and I have a fix it ticket for registration. The only thing holding me back is getting this car smogged so I can clear my fix it ticket and get my reg. sticker. I've been trying to do it myself but I guess I may have to find a mechanic which will be painful because the car is not worth all that much.

I do like this car though. I would love to get it running well. At times it does seem to run perfectly if it weren't for those warning lights, failure to start, and weird idle issues.

Well, I appreciate you reading all this. If you guys have any suggestions please let me know. Also, if you know of any good/cheap mechanics in the SF Bay Area let me know.

Best Regards,
RC

 

Have you checked the following
Vacuum hoses for cracks or breaks
Hose that connects the MAF to the throttle body If it gets even the smallest hole it will not idle good.
Has the fuel filter been changed.!!!!!!!!!!!!!!
Is the cylinder compression good.
Something is causing the Check engine light come on, if you cannot pull the codes it is hard to head in the right direction to pin point the problem. With the age and miles it could be several things. I hate that you live in a part of the country that requires a vehicle that old to pass an emissions inspection. did replacing the Distributor o-ring fix that oil leak. If it is still get an oil film on the Cam Postion sensor that will cause hard starting and rough idle