My car all but died and won't wake back up!?!
 

My car has been running very well for the past few months and all of a sudden today something happened. On the way to work, it was fine. On the way home for lunch, it was fine. I was driving back to work after lunch when I noticed the exhaust popping a little more than usual, and then when I got to work and pulled into a parking spot, I noticed it idling at about 500 RPM instead of the usual 800. It was so quiet that I could barely hear it running.

When I got back into the car to leave work, I started it up and it was popping and missing and had no power in the lower RPM's, and was just all around running crappy. The weird thing is that once I got up to around 3000 RPM, everything seemed fine until I let off the gas and it started backfiring all over the place through the exhaust. My first thought was that maybe a plug wire had popped off or a vaccum line had become disconnected. Of course it can't be that easy. I didn't have time to really try and diagnose it because I was trying to get to school (I go straight from work to school). I popped the hood and had a look around and didn't find anything obvious out of place.

It starts right up every time, and never stalls, but something is definately wrong. I know I should scan the codes before really trying to diagnose it, but I figured I'd post this in case someone has experienced this before. Between school and work (military), I don't really have much time during the week or on Saturday to do much, so I need all the ideas I can get ahead of time to try and squeeze them all in on Sunday when I'll try and fix it. Any ideas?? See sig for mods.

Dave

My initial thoughts were MAF meter, but you might not have one being an 88'. Is your car speed density or mass air flow?

My car has been converted to Mass air. I use a 73mm C&L with the 24lb sample tube. I thought about that as well, but hoped that wasn't the problem. The code scan should throw a flag for that when I do it. I'll be driving my wife's caravan until I get this resolved which is our only other vehicle, so hopefully this won't take too long. :rolleyes:


It's kinda funny actually because just last week I was telling my wife "The car's been running great for a while, so knowing my luck, it's about time for something to go wrong with it." I think I jinksed (sp?) myself.:mad:

I'd look into the MAF too. Popping in the exhaust, especially when letting off the throttle, is typical of a lean condition, and having it go away at higher rpm's had me thinking vacuum leak, but a vacuum leak will cause a stall during a hard stop, and you said it doesn't stall, so I'd look into the MAF.

Of course, I'd pull codes first.

:)

Take care,
-Chris

My car burns oil in 2 cylinders, and will foul a plug now and then, and when it does it sounds very similar to what is happening to you. It will come on over the course of a day, with the car running just a bit rougher, and then next time I crank it, stumbling, popping, etc all over the place. My first instinct would be to check the plugs.

Just my $.02,
Jorge

UPDATE
 

Well, I came back into town tonight and scanned the EEC for codes, but nothing out of the ordinary came about on the KOEO test. 81, 82, and 85 were there, but they always are because I have no emissions equipment. There was a continuous code of 51 (ECT), but I have no idea how old that is so I disconnected the battery to reset the EEC, and I'll scan it again tomorrow night.

The weird thing is that I tried a KOER test a few times, and it just beeped 5 times, and that was it. 5 is not a recognizable code, so I don't have a clue what that was all about.

I had to keep restarting it and keep my foot in it to keep it running until it warmed up and then it idled really low (about 500rpm) just like it was when I made this post.

If the 51 dissappears, then what should I look for?

I know the MAF was definately a suspect, but wouldn't that code have come up? The plugs all look fine and only have around 500 miles on them.

any help is greatly appreciated. I really would like to have this fixed by this weekend so I can attend a good friend of 5 years' graduation. I promised him a ride in the stang when he graduates over a year ago, and I don't want to let him down.
Thanks in advance,
Dave

this happened to me too..
 

This probably doesn't help you much but, I had to pay someone to "look the other way" when passing my smog, and in doing so, they screwed my timing up really badly. I think they adjusted the timing somehow to pass me, and never put it back to the original setting of 10*. :confused:

I would absolutely love it if that were the case. Unfortunately it isn't this time. My timing is at 14 and I haven't changed anything as far as the state of the tune of the car in about three months. I didn't put a timing light to it to ensure it hasn't jumped timing, but because it fires right up every time with no problems, I don't think the timing has moved. I didn't check it last night however.

Can anyone tell me what voltages I should have at the MAF from the four wires connecting it to the EEC? Is there any other way to test it?

I had the same exact symptoms one day and it was caused by the ACT. Since the ECT is similar, I would just go ahead and replace it. You may want to check the ACT as well. Start small and worry about bigger stuff later.

Thanks Jim,

I'll replace them both and see what happens.

another update
 

well I replaced the ECT and the ACT sensors and then fired the car up. It still ran like crap at first but didn't stall like it usually does when it's cold. The idle would drop until it started to stall, then it would rev up to about 2500 real fast as if I pressed the accelerator, and then drop down to around 600 or so.

After about a minute of that, it started idling normal. I was extatic!! I took it for a test drive and it ran great for about 2 miles, and then it started the same old crap again. It's in the same condition it was before I replaced the sensors.

I scanned for codes again and got 81, 82 and 85 like I usually do, but had a continuous code of 15. I think I misinterpreted it the first time as being 51. I had disconnected the battery and cut the headlight switch on and left it for 30 minutes while installing the new sensors.

I'm lost again. I hope my EEC isn't fried because I just bought it less than a year ago. I've read that a code 15 (KAM) could be from a short in the wiring, a bad EEC, or from disconnecting the battery. That doesn't really narrow it down too much since I disconnected the battery to reset the EEC. I'm gonna pin out the EEC with a DMM to check the voltage with the KOEO, and that should hopefully tell me if it's an EEC problem or an wiring problem. Any other suggestions?

That's a real easy test, but in case you aren't sure, I'll tell you what to do.

1) Disconnect the 60 pin connector from the ECM.
2) Test for KOEO voltage between pins 1 and 40 or 60 at the 60 pin connector. If you get 10.5 vdc or more, the ECM is bad. If you don't get 10.5 vdc, start tracing the wires and find the open circuit.

Take care,
-Chris

I think you get the code 15 if you don't disconnect the battery long enough for the KAM to be completely cleared.

How long did you let the car idle after it started idling properly? How did the sensors you removed look?

The sensors looked fine when I removed them. The ECT was only a few months old and neither one had any apparent corrosion or crud on them. The contacts all were very clean for the most part.

I started the car after reconnecting the battery and let it idle for about 1.5 minutes and I noticed it was running better, so I took it for an easy test drive for about 2 miles. During the drive it started running like crap again so I disconnected the IAB, and it shut off, which I assume means it's working, then I fired it back up and checked the TPS and it was fine, and the timing is still at 14.

The sensors looked fine when I removed them. The ECT was only a few months old and neither one had any apparent corrosion or crud on them. The contacts all were very clean for the most part.

I started the car after reconnecting the battery and let it idle for about 1.5 minutes and I noticed it was running better, so I took it for an easy test drive for about 2 miles. During the drive it started running like crap again so I disconnected the IAB, and it shut off, which I assume means it's working, then I fired it back up and checked the TPS and it was right at 1 with no throttle, so I adjusted it down a little, and the timing is still at 14. Basically I was just shooting in the dark at that point.

Try giving it some time to relearn the idle. Once it starts idling, let it idle for 10 minutes without intervention. Then shut it down for 5 minutes. Start it back up and turn on all accessories if you have any and let it idle for another 10 minutes.

Do all of this after resetting the computer. See how that works for you.

Did you ever check the MAF meter voltage? You might want to set your timing back to 10 degrees until you get it worked out.

No, I haven't checked the voltage on the MAF yet because I'm not sure what it should be. Which of the four wires should I test and what should the voltage be?

Theres 4 wires, labeled A,B,C and D. They should be labled on the plastic piece. If not, let me know.

Wire D is the MAF SIG, or Signal to EEC-IV module.

Wire C is the MAF return or Signal return.

Wire B is is the vehicle power ground.

Wire A is the VPWR, or vehicle power.

1) Test VPWR and Ground:

With key off, disconnect MAF connector
- Connect DVOM (digital volt ohm meter) between VPWR and GND at harness connector
- turn key on, leave engine off

You should have 10.5 volts or greater.

If not, theres a fault in VPWR ciruit or in GND circuit to battery.

2) MAF circuit short to ground:

Key off
Connect DVOM between MAF SIG and MAF RTN, and MAF SIG and GRD at harness connector

Results- 10,000 ohms or greater

if not, fault in wiring to control unit or faulty control unit. (EEC-IV)

3) MAF sensor voltage

MAF sensor connected
- backprobe MAF sensor connector between MAF and battery negative(-) terminal
Engine running

0.2 to 1.5 volts dc

If not, MAF sensor may be faulty

Well, here's the results I came up with.

the pin 1 and pin 60 readouts were 11.88 KOEO and 12.11 key off.

test VPWR and GND - 11.72

MAF SIG and MAF RTN - no reading

MAF SIG and GND - no reading. Anything that involved the SIG (D) wire, got no reading whatsoever.

backprobe MAF - have no idea how to do that.

A quick lesson on DMM's probably wouldn't hurt anything either. I just bought my first one today. For ohms, I set the DMM to 20K, so if that's not the right setting, then call me an idiot and tell me the correct setting. ;)

You should have a reading when you do the second check, so I dont think you are using the meter correctly.

Make sure you switch it to "ohms" (which measures resistance) and didnt leave it on "volts DC" which you needed for the first check.

Most meters have AC volts, DC volts, continutiy, ohms, AC amps, and DC amp settings. When measuring amps, you switch the one lead to a different hole on the meter.

But thats more than you need to know.

To backprobe, get a piece of wire or a pin or something and pierce the insulation on the wire, so you can take a reading with the connector connected to the MAF meter. then touch the wire or pin with your meter lead.

well, I knew I was looking for resistance (ohms), but it's not labeled on the MM. I made sure that when I touched the two pins together and it came out to 0.00, so I figured it was on the right setting.

I took the car for a drive and came back and checked the plugs again. What does this tell me?

Plug looks like you have a very lean condition, but it's hard to say for sure. i know you're going in several directions at once, and I don't want to confuse you, but that code 15 is pretty important. You said you disconnected the battery and turned on the headlights for 30 minutes. That should have been fine. Do that one more time, but this time, just before you reattach the battery, touch the disconnected negative cable to the connected positive cable post on the battery (MAKE SURE THERE IS NO CONNECTION BETWEEN THE NEGATIVE BATTERY POST AND THE VEHICLE), and pull KOEO codes again. That will absolutely clear out any residual, measurable electrons from the system. If the code 15 returns, the ECM is damaged.

Take care,
-Chris

PKRWUD,
I just came in to post some more info and read your post just now. I swapped EEC's with a friend and it made no change. After I reconnected mine, and started it and let it run for 10 minutes, I shut it off and rescanned KOEO. The continuous code of 15 was gone. It gave me an 11 in the continuous code area between the seperator beeps (is it supposed to do that?)

I started it back up and while it was running (barely) I unplugged the MAF and it ran much better. The sputtering was gone (of course I didn't drive it, but it revved much better.) I'm assuming that the MAF is bad?

code 11 is the everything is ok code, if my memory serves my correctly.

So code 11 is a good thing.

If you unplugged your MAF meter and it ran better, that would seem to indicate a faulty meter, as logic would dictate it should run a lot WORSE with the meter disconnected.

But, it could be your ECM. Did you try swapping MAF meters with your buddy also?

I knew 11 was the "okay" code, but I didn't know it was used as a continuous code.

I couldn't swap with my buddy because I have his EEC. It's been sitting in my garage for a month because his car is parked in a storage lot (he's overseas), and he yanked it for me to hold it so no one would steel the car.

I went to the store and bought a new MAF and it seems to have fixed it! I just took it for a ride and it's driving better now than it ever has. It doesn't pop at all when I let off the gas with it in gear. It used to pop some when slowing down and in gear. Hopefully it will stay this way. Thanks for your help guys.

Dave

Wow Drastik, your problem sounds exactly opposite of mine... I hope you get yours fixed soon... I know what a pain it is, but with all these people helping us, it's only a matter of time! :)

My car was running like crap. In the mornings, it would pop back, spit and sputter and had absolutly no power. After it warmed up a little, it ran better but never at 100%. I thought it was my timing was off because of the way that the power would dip if I pressed the trottle and i had spark knock really bad. The timing turned out to be right. It was on 14. If i dropped it back to the stock 10 degrees, i was sure to get smoked by a kia....it was that bad! After reading this thread, I decided to buy a can of carb. cleaner and take the mass air off to clean it. The diodes looked a little dirty but not real bad. I cleaned it anyway and now I am restored to 100%. Not sure if this will help you any but i would give it a shot. It beats buying replacement parts when you dont really know what the malfunction is.

Thanks to all who posted messages in this thread!!!!

interesting, I used carb cleaner on mine, and it ran like crap, cleaned it again with alcohol, and it ran better.

I think the oil on K&N filters tends to get sucked into the intake path and coat the MAF sensing element. The Pro-M web site recommends using a pipe cleaner to clean the sensor.

I like Mach 1's suggestion. Use alcohol. Alcohol will displace the oil on the sensor so that it can be washed away and then dry quickly with no residue.

I have a question.

What exactly does the Idle Air Controller do? I went to replace it and after I did, when I accelerated the rpm's would not drop back down for at least 5 seconds. I have been told that this would be caused by a bad TPS switch, but I replaced that before I replaced the Idle Air. When I removed the old Idle Air Controller, it had oil inside. Is that normal?

The Idle Speed Control solinoid allows air to bypass the throttle plate in order to maintain idle. It modulates this airflow in order to keep a nice stead idle. Disconnecting it shuts off this air supply, which is why the car should die or at least stunmble if you disconnect it while idling.

Checking the voltage throughout the TPS range would be a good idea. Also check the return springs to make sure somehting's not binding. alos, be certain to disconnect the battery for at least 10 minutes after replacing sensors to clear the Keep Alive Memory that the computer has stored info in. It could take several miles for the computer to figure out a new configuration.