94 Mtx Few issues

[MadMiike]

Ok so here we go. First problem is my CEL only comes on after about 15-20 minutes of running and has for the past year. I can shut the car off when the CEL is on and restart it and It wont be on But will come back on again after a another 10 minutes or so. Any ideas? Secondly I have noticed a power loss only under load. In neutral it is fine. It stutters badly if u mash the gas before 2500 rpm. If I accelerate slower is seems to be better but yet still has like a "surge feeling" About a week ago I scanned the car with a koeo NO Codes. Then did the KOER and got the codes 565 canister purge solenoid and 172 (M) Oxygen sensor not switching - system was at adaptive limits - Single,, Right or Rear HO2S - Fuel control. I cleared the codes went to scan it again yesterday at work and I cant get any codes. Here is a list of newer things I have installed O2 sensors, Maf, Platinum plugs and wires. Removed throttle body and Iac and cleaned, coil pack and many other things that don't pertain to this situation. :banghd:

 

[93rev2sev]

Having cleared the codes, I would expect that some will reappear. Keep checking them.

That canister purge code that you got should be dealt with. This system can be a pain to diagnose and work on, but I've heard of drivability problems due to faulty systems.

Even though you've replaced the MAF, unplug it and drive around for a bit. If the chugging and missing continues, you can be sure that you didn't get a bad one (as your codes would indicate). Clear the codes again after this test.

If you keep getting the O2 codes, swap in a known good one, clear the codes again.

If it keeps chugging and jerking, suspect the plugs or wires.

Get ohm readings on all the wires. You can use just about any run of the mill multimeter for this, but an analog guage type multimeter will allow you to see if the reading changes if you flex the wire. If there is an intermittant short in the wire, the needle may spike when you wiggle the wire.

Did you gap the plugs when you installed them? What model plug did you use? These cars are sensitive and don't like gimmicky plugs. They like standard double platinum plugs like the Autolite APP3294 and the Motorcraft AGSP32FM gapped at .042 - .046 inches.

 

[rubydist]

The cel will come on for the adaptive fuel at limit issue. Just because you put in new o2 sensors doesn't mean that they are good, or that the wiring to them is good.

You could also have dirty injector(s) based on your symptoms. I would put in some good injector cleaner for the next 3 tanks, (or about 5 oz of acetone per tank as I use for injector cleaner.)

I have also had weird symptoms like that without necessarily having a cel from a bad or sick tps - you might consider getting a new one of those as well. The tps is a very important input to the pcm, and if it thinks the throttle is closed when it is not, it will run lean and not have much power, sometimes bucking and lurching. When the tps is very bad, you will get a code, but not if its just sick.

 

[sperold]

Due to the strict emission laws, the check engine light has to be off here. I found the only O2 sensors that work well were the Motorcraft. A shop put in some brand X sensors and the check engine light would come on under 2000 rpm. It would stay off all day if you were on the highway going over 2000 rpm. With the Motorcraft, it passed the test. All the others failed (and there were quite a few).

 

[MadMiike]

So I been working on the SHO when I had the time the past few weeks and am not having much luck. I wasn't able to get the scanner back on to get codes until yesterday. Due to the scanner being broke at work and only having OBD ll Kia ones Anyways the codes it gave this time were 136 left front heated o2 lean and 172 Right rear o2 lean. And also 538 which is the "Snap Throttle" or "Goose" Test otherwise known as WOT test. It would not perform this test and scan says replace Pcm. Could this be my problem? The car is no longer really even drive-able. It does drive but when I start it I have to crank it and cycle it about 5 times to get it to start! Probably parlty cuz its 0 degrees. lol. Then when it warms up it has absolutley no power! ( Cant even spin in the snow) I also did a Fuel pressure test all was good. Did a Back Flow test to see if it was Cats..All was well there. Intake is not leaking. No oil in plug wells! No voltage problems. ALLDATA says possible causes For these 2 codes could be

Fuel Injectors- Ran a few Injector cleans in the past 2 months
o2 Senors- Both are new as of 9 months
Secondary Air Injection- Did check they do open.
Vaccum Leaks- found 1 broken T and fixed it.
Evaporative Cannister Purge- I got this code the 1st scan but Not on the 2nd
Manifold Absolute Pressure Sensor-
Electronic Ignition Coil Failure
Positive Crankcase Ventilation

Where would be my best bet to start?

 

[rubydist]

Having had these symptoms and no codes or no codes other than what you have, I will suggest you replace the tps. Then, reset the codes again. Then, perform the idle reset procedure. Then, see what happens next.

The most effective way to make one of these SHOs into a gutless wonder is to have the tps go bad - it will tell the computer that the throttle is closed and that it shouldn't believe the mafs readings it is getting because there simply cannot be that much air there with the throttle closed. Consequently, the engine will run crazy lean and have no power.

 

[MadMiike]

Ok thanks I ordered a Tps from O'reillys this morning. Good thing my gf is the Asst. Manager saved 23 Dollars I should have it Friday so I will let you know what happens.

 

[MadMiike]

Ok so I replaced the Tps and also put in a good working MAF and also reset the idle. ( Idles a little better) but still no power! When I say no power I mean Mashing the gas to the floor and it just goes baaahhhhhhhh and thats it. But once I back off the throttle to about 1/8 or 1/4 throttle it picks itself up a bit. So Im guessing I might as well replace the O2's! Any other info on the situation would be greatly appreciated. As I am just lost! UPDATE: Just went to start the car turned over and started on the 1st crank idled real low ( 400-500 rpms). Let it idle about 5 minutes then went to give it some gas and died. Tried to crank it over wouldnt start. So I put the pedal to the floor and it starts But immediately had to let off the gas. So basically the car only idles and runs "Ok" under quarter throttle.

 

[93rev2sev]

If you've unplugged the maf for test driving purposes and swapped in a good DIS and coil pack then there's a decent likelyhood that the ECU is the problem.

 

[shotyme92]

Have you replaced the fuel filter or dropped the tank to see what the fuel pump pickup screen looks like?

 

[MadMiike]

I did replace the Fuel Filter about 6,000 miles ago. I have not checked the screen. I really dont want to drop the tank But as soon as I get it over to work I will check it out.

 

[shotyme92]

Not that hard to drop the tank. Took me about an hour to drop tank put in a new fuel pump and put it back in the car. Maybe pull the fuel filter out and tap the inltet in the ground and see if you get any material or dirty gas coming out before you drop the tank. Might save some time.

 

[MadMiike]

Ccrm

So I scanned my car a few days ago and got the code for Fuel Pump relay circuit failure. So I ordered a new aftermarket one from Napa AND put it on my car. I put the Module in then put the battery cables back on and the cooling fan kicked on immediatly. So I pulled the cables off and tried again same thing, besides this time I went to start the car and noticed a a smell. Well it smoked the new CCRM. So I warriented it and got a new 1. Tried again and same thing. Why would this be happening? Do I have a short somewhere? :thankyou:

 

[rubydist]

Fuel pump codes often appear after the engine has stalled, and those can be ignored.

It sounds like your friends at NAPA have given you the wrong ccrm - they are not interchangeable and you must use the proper letter code ccrm or things will not work.