I need some help from people more experienced than I. When cold my 89 starts and runs fine. After about 20 miles, it starts losing power and will bog down when trying to accelerate to pass... no kickdown, and a rough idle. After about 30 miles, it will barely pull a hill and acts like it is dying when I depress the gas even a little. When I shut it off, it will not restart. The only code I get is a 44 which is a lean condition on the motor.

I just got the car and would appreciate a good starting point. Thanks in advance.

Alan

Welcome to the site, the guys that know a lot about everything will be here soon. You will get it figured out. I'm thinking fuel pump issues but they will know what else.

There are the basics... I would start with a bad fuel filter... it's cheap and should be done.

The filter is located on the passengers side of the car, inside the frame rail, just behind the RF wheel. Yea, it's a bit of a bitch to reach... sorry...

The pump? Maybe... Do you have access to a fuel pressure gauge? If not, you might want to get one and see what the pressure is doing.

Pressure should be pretty steady at about 43~45 psi...

44 also indicates a lean which can be a bad O2 sensor.

Welcome to the site, Alan!

#1, you're ahead of the curve by already having the best year C4 out there (see my sig )

#2, you didn't really provide too much background info, but I will try to help you the best I can.

A code 44 means the oxygen sensor circuit is indicating a lean exhaust condition. According to the FSM (which I highly recommend getting), the following diagnostic aids are related to that:

1) O2 sensor wire
2) intermittent ground
3) MAF sensor
4) lean injectors
5) fuel contamination
6) fuel pressure
7) exhaust leaks
8) AIR system

Based on personal experience and from others having problems, the first place I would be looking is the fuel system. Has it been maintained? Do you have a fuel pressure gauge? If not, go to Harbor Freight and get this one:
http://www.harborfreight.com/fuel-injection-pump-tester-92699.html

You need to know what the fuel pressure looks like, and do a comprehensive test as outlined in the FSM (I can help with that later). I have a feeling the fuel pressure is dropping or is too low and that is causing the lean condition. This could be a result of several different problems, either alone or combined:

1) Fuel pump is weak (they are fuel cooled on our cars and
when the tank is less than 1/4 full repeatedly they tend
to burn out) or bad check valve
2) Clogged fuel filter
3) Bad fuel pressure regulator
4) Faulty injectors (the multec injectors in our vintage
break down due to the ethanol in newer fuels)

I would test the injectors with a DVOM. Pull the injector clips off of each injector and place the probes on the metal tabs inside the injectors. You should do this both with the engine cold and hot, as when the internal coils heat up they can short out.



Start here. I have a nice post in the tech library about replacing the injectors in the 89, as well as a post about replacing a fuel pump. I should also have a post somewhere with the FSM fuel pressure tests. There is a lot of good info on here, so keep us updated.

Matthew

Thanks to all of you for the starting points, your inputs are greatly appreciated. As I said, the car runs fine at first but after I drove about 45 mins today, it became less and less responsive. When I'd step on the throttle, it reminded me of an old Quadra-junk with a bad accelerator pump. With all of the electronics, I just need some experienced advice.

Quote:

Mine is black as well and the rims look similar but my back ones appear a little deeper. Bone stock right now but it does have a fiberglass cowl induction hood that looks nice...gotta get it running as good as it looks.