More Woes

[Howard]

Well, I thought perhaps after being in the shop for months, my Reatta was fixed. Wrong! I spent most of Saturday getting it all nice and clean and went on a few weekend errands, ran great. I also had the oil and filter changed and a new state inspection. Returning home, the car just died like before. This time is did set a code E042, no others. I managed to limp home. I do have a spare ICM and coil pack, so I replaced them to no avail. Would only stay running less that two minutes and die, but would crank again, run for a few minutes, then stop. I've not tried today. I've checked the wires at the ICM connection and at the ECM, I don't see any issues. I still think the problem goes back to when I had the harmonic balancer replaced and something is not right with the crank sensor. Looking through the shop manual, I don't see any kind of test for this sensor, nor does it set a code that I can find. I'm I correct? This problem has me stumped. Most of the time I can figure out what is wrong, but this time I don't have a clue. I've thrown alot of money at this problem with no joy.

[Guest maybe2fast]

not sure what code 42 is, but sounds like a crank sensor.

[Guest F14CRAZY]

From my experience, the crankshaft position sensor either worked or didn't. Not really anything in between.

[2seater]

E042 is the spark timing circuit (EST). ECM, maybe, or possibly a harness problem? You tried a different ICM, one of the items the diagnostic tree leads to, the other is the ECM itself. Make certain you press on the ends of the connection at the ICM when you tighten the screw. The EST circuit is near one end of the plug (white wire on pin A)and it is quite long so the screw doesn't necessarily tighten it fully. The harness runs across the front of the engine and connects to the cam and crank sensors as well. There is another large connection near the right rear corner of the engine where it connects to the harness that goes to the firewall. The problem does sound like a possible crank sensor, but it is acting oddly for that to be the case. If one of the signals from the crank sensor is lost while running, it will continue to run but in the limp home mode. Usually if that is the case it will not restart, it must have both signals to start the engine. It may be temperature sensitive, causing loss of signal when hot and making the connection again when cooled? I do not believe that will set the code 42, it is either an open or short to ground on the EST wire.

[Guest DTerry]

Howard, this may be reaching a little, but I've had two cars have fuel pumps that would shut down when they got hot. Let it cool a few minutes and would start and run for a while, then shut down again. As long as I kept the tank over half full all was okay, but when it would get below half a tank there wasn't enough cooling. What was your fuel state when it quit?

By the way, one of them is my old Caravan (249000 miles), and two weeks ago it failed to start for the first time ever. I've been driving with the bad fuel pump for at least 4 years, and it finally just gave up altogether. (It'll sit until the weather warms up.)

[padgett]

Have seen a crank sensor with one of the magnets broken half off (there are three). Believe it did run occasionally. Is why I built the breakout box - can look at the output with an o-scope. Is kind of a square wave.

[Howard]

Update: First, as always, thanks to everyone that is trying to help me. That's what makes the forum so great, is everyone willing to help each other out. Thanks for the tip on the ICM. I did tighten the center screw, but did not hold the ends. I took it off twice today (along with checking the ECM connections), but will remove it tomorrow and use the hint. The first time the car shut down in October, the car had about 1/4 of a tank. Yesterday, I just filled up. The shop did test the fuel pressure and found it to be OK. I noticed yesterday there was a strong smell of unburned gas, like an old carb equipped car that was running too rich, when it started acting up. I don't think it is a fuel issue, because that would not have set a code E042. Today it started right up, but noticed at any RPM above about 3000, code E042 would set. At about that engine speed the car would start to miss, not shut down, just start to miss and seem to backfire sort of (it did that yesterday too), until the RPM dropped below that number. Again, when the car started to miss, I could smell what was like a rich mixture. I let the car sit idling for about 30 minutes and ran fine at about 600 RPM. Took it for a drive, keeping the RPM below 3000. Once above that RPM reading, the "service engine soon" light would turn on and code E042 was set as "current". After about 30 minutes of driving, the code was set at about 1500 RPM and the car ran badly. I did manage to get home, below the speed limit. I don't think the problem is the ICM itself, because I have a spare, and the car behaves the same way with the spare. The ICM on the car now, was purchased in October along with the crank sensor. Maybe I can sort this problem out someday, I hope sooner than latter as I miss driving my old friend. Again, thanks to all!

[tc11003]

have u pulled the plugs ? to see whts going on there?

[Guest kennyw]

might it be a harminic balancer going bad and at higher r p m hitting the crank sensor? You seemed to have tried most everything else. ken

[manikmekanik]

Check wire harnessessesses to the cam and crank sensors, I've had to replace the cam harness before, due to it "rubbing" on the nearby bracket(s).

Or, as earlier suggestion, look for cracked/loose crank sensor. Wiggling can cause similar troubles.

[padgett]

Have been having this niggle in the back of my mind that EO42 is set by the ECM and a bad inpt line will do it also. Have you tried swapping the ECM ? What happens is that when it sets the car runs on the Ignition module and the EST signal is actually going from the ECM to the Ignition module. If the ECM stops sending the pulses, the ignition swiitches to a "get home" mode but if the crank sensor or the ignition module had failed, the engine would probably just stop.

Book talks a lot about the ignition module but if you have swapped that the next thing to try is the ECM. Do you have a spare ?

[2seater]

I agree with Padgett that it is pointing more and more like the ECM is going south. There is a diagnostic "tree" in the manual to help sort it out, and if you cannot find a physical problem with the harness or connections, I would suspect the ECM. Since it seems to run for a while, and then acts up, you might try pulling the ECM and let it lay on the floor where it will stay cooler to see if the behaviour changes. Not the best but mine has been like that for two years to make it easier to change chips and I generally don't have a passenger The fuel pump won't set a code, but it is possible it has enough fuel for low speed and cannot supply enough for greater load. The only way to know for sure is to be able to watch the pressure while driving. The harness on the front of the engine is very common in the 'yards. You can wiggle the harness or connections if you are taking voltage readings with the engine off but unfortunately it would be very dangerous or impossible with it running. I do not know what the timing advance would read in diagnostics if the EST circuit fails? If it is something like 10 degrees or so while idling it is no doubt not working, but I do not know where the diagnostic will pick up the reading when in failure mode?

[manikmekanik]

I did'nt intend for anyone to try to wiggle the harnesses while running, though I'm sure one could, using a remote grabber, or even a string, run away from the moving pulleys.

Bear in mind, the main connections for electronics ground and positive are on the fender, buried by the battery, either of these could be corroded, causing bad signals or shorting out altogether. Many folks never see them, and they go un-noticed/unchecked.

When I had a similar problem, I used my multimeter to test wiring while wiggling the harness-with the engine off, for continuity. I also tested for signal voltage with key "on" engine not running.

This is how I found bad wires in the cam sensor circuit, once they were repaired, I was able to eliminate them from diagnosic search set.

My final problem was the ECM, and yours may be as well, but I would check all grounds and harnesses to/from the ICM and ECM before investing cash in a replacement unit, rather than time to pinpoint the problem.

[padgett]

Just as a suggestion, a good "experienced" ECM is usually about $30-$50 (with PROM) and is something that is good to have just in case. 1228253 aka 16198264 ECMs were in every "C" 3800 and are millions around (get the PROM becaue is easy to reblow, just use the one from your original). If you have trouble finding one, let me know.

Sometimes it is easier to just swap parts particularly if you do not have all of the testing tools.

Have my doubts that it is a ground because everything else seems to be working. When the error sets it seems the EST signal is the only thing that has been lost because the engine is still running which means the ignition module is still firing the plugs and the ECM is still firing the injectors. All that is screwed up is the advance map which is corrected by the ECM and sent to the ignition module on the EST line.

[Rattaboy]

Howard, Here's a far reach for you. Several years ago I had the filter/strainer on the in-tank fuel pick up (Olds) get plugged after some bad gas (trash, varnish, whatever). It acted as you described your problem. Like never to have found it.

[Howard]

Answer to some questions: No, I've not checked the spark plugs. New ones had just been installed as well as wires when I bought the car 1998. I've put about 70000 miles since then, so yes the plugs should be replaced. However, when the car runs, it runs very well, even at high speed. I don't think bad plugs or plug wires would set a code. Am I correct? I've not checked the grounds. This is advise I've given to others with electrical problems, yet I've not checked that issue myself for this problem. I will take a look, just for the heck of it. While I do have an extra ICM, I don't have a spare ECM. The ECM was replaced in 2001. At that time the car would not start period. I might check with Jim Finn to see what he may have in ECMs. I'm still leaning to a wiring issue, yet I've not seen anything wrong. How hard would it be to change that harness? It looks some what like a bear. As to the fuel issue, yes I would agree that the way the car was running the last time I drove, it did seem like maybe a fuel issue, but I still keep coming back to the fact that if that were the case, no code would have been set, at least not the one that was set. I've not worked on the car since the weekend, but next weekend, I work some more and report back. It will be interesting to find out just what is causing this nagging problem. I've said it once, and I'll say it again. Thanks alot for your help. You guys are the greatest.

[Machiner 55]

Check this link

[Howard]

Thanks for posting the link. I do remember your post from last year. This weekend I changed the ICM back to the one I took out in October, with no improvement, same code and poor running. I don't have an extra ECM to try. I'm going to contact Jim Finn and see if he has one. I hate to pay for a new one, and that not be the problem. Once used, the auto parts stores won't take the part back. I hope my problem is something as simple as the ECM and not some kind of wiring issue which is what I fear the problem to be.

[manikmekanik]

Hi, Howard!

I was able to secure an ECM from AutoZone for @$80 w/exchange, not too bad for a reman? unit. Being a sealed unit, you may be able to get one from a local "flood/hurricane" damaged car, or even the whole car, cheap. Might be worth a try, check with your local boneyards.

[Guest F14CRAZY]

Oh I don't know. They're not really sealed. I wouldn't trust an ECM from a flood car

[Guest imported_Flash]

Howard,

Sorry to hear of your continued problem. I have certainly appreciated your concern and help with my occassional incidents.

As unlikely as it may be, have you assessed the catalytic converter. My only reason for adding it, is your mention of the 3000rpm threshold where above is bad but below is better. The behaviour of your vehicle appears to be dependent upon speed and if that is true, then cc's can severely restrict performance. As an test driver at Milford in the early 80's, I drew a Century with a plugged converter one night. I was running a transmission schedule (my test assignment for that shift) and couldn't get over 45mph and finally had to be towed into the garage.

Hope you get things worked out soon.

Flash

[Howard]

I vote with F14. The ECM is not sealed at all. While I'm sure such a part could be purchased for a song, I would not trust any such part exposed to flooding. During my days at dealerships, I saw cars with very little water damage have to have a lot of money spent on electronics just to get them running again. Water is not a computer's friend. I have not contacted Jim yet about a used one, but will. Thanks for the insight however.

Actually, I did think perhaps the "cat" maybe causing problems, but I've dismissed that because I don't think a clogged "cat" would set a E042 code and at times the car runs fine. If the car had a stopped up converter, I think it would run badly all the time.

I think the problems are caused by one of the following items. I still can't help but think there is still a problem with the Crank Sensor installation. After all, my problems started with the harmonic balancer replacement. Or, a wiring issue. Finally, a bad ECM. The Crank Sensor or the ECM would be a simple fix, the wiring , I better take out a bank loan for that one. Wiring issues are the hardest to track down and one of the most costly from a "flat rate" prespective. I'll provide more info as it occurs. Again, I'm very grateful for everyone's help.

[padgett]

Depends on the water. I have seen electronics immersed in fresh water come right back once dried but salt water really does a number.

[Howard]

Update #2: I just installed the "new" ECM I got from Jim Finn. Sorry to say, no joy! Car is still running bad and stops, but no codes this time. Also the PROM included with the ECM is the wrong one, since my MPH was showing 124. That's what I call an boast in performance . I put the old ECM back and the reading was correct. Anyway, it's back to the drawing board. Will report back any new findings.

[padgett]

Sounds like you got one with a 1990 PROM - what was the letter code on the silver foil on top of the PROM ?

Did you try putting your old PROM into the new ECM ?

[Howard]

I did replace with the old PROM, and the speedo did work correctly. Now if the car would just run correctly, I would be in business .

[Machiner 55]

I agree with Padgett. The PROM (mem-cal) that came with the car, should stay with the car.

At least now you've eliminated the ECM as the culprit.

[Howard]

I was really hoping that would be the "fix". There may have been, but I don't recall, anyone having posted about their Reatta taking this long to find a repair. I'm going to re-read all the posts you guys have provided me and start again from there. I will provide more updates as they occur. Again, I can't say it enough, thanks for everyone's help.

[Howard]

Update #3. Well, I think the problem has been found and resolved. Note the word "think". The problem was the new harmonic balancer! It seems that one of the teeth behind the HB was slightly bent. This caused the crank sensor to be worn away. The bend was ever so slight, you really have to look at it closely to see that it is indeed askew. So after over 6 months, a new coil pack, ICM, and a known good ECM,(of which none of this was needed), and a bunch of money, I'm back on the road again. I just drove it to a city about 20 miles away (40 round trip)and all seemed well. There seemed to be more rattles than before, but the car seem to run OK. Now I have to see if the other shop I took it to the first time will refund any of my money. My guess, it will not, but I'm going to try. I had to pay for this same repair twice. I hope that this is the last update I'll have to make on this issue. Thanks to everyone who offered advice. I'm glad to be a Reatta driver again.