I have an intermittent and ongoing issue that has finally become regular just this week. I have had ETM light turn on several times over the course of the past few years. It is usually random and it may be linked to jumping other peoples cars, that I have noticed.

I have replaced the upstream O2 sensor, and the MAF sensor. Also the thermostat and the temp sensor (all aftermarket).

I was driving home from work after jumping someones car for about 40 minutes (I left it running while I troubleshot his 2002 Chevy Blazer that turned out to have a wet air filter suffocating the intake), then drove home. Almost to my exit about 20 minutes after leaving, I lost power entirely to a stall going about 75 mph, and coasted to my exit off the turnpike. I pulled over and yanked the MAF sensor cord off and drove home.

I chalked it up to another quirky electrical issue from charging that persons car, and recharged my battery, cleaned the MAF and cleared the codes. It drove fine to work, relatively, with barely noticeable turbo hesitation, but I chalked it up to the car adjusting fuel trim, etc. On my way home that night, it lost power on the turnpike at around 70 mph, but this time it didn't stall out. I removed the MAF sensor cord again and drove home (I removed it because the car was in limp mode, and that's very dangerous on a highway).

So after two days reading about the issue this is what I have done to begin to diagnose the issue:

Prior to the drive I made sure to clean the MAF with appropriate spray and let it fully dry out. I noticed the ENGINE MANAGEMENT RELAY case was cracked on one side (maybe due to previous owner inspecting the coil), so I removed the relay carefully and noted that two out of the four prongs were black. I also removed the AIR PUMP RELAY and sprayed electronic cleaning spray on both of the prongs and to where the relays plug into the car. I did all of this with the battery disconnected. I let them set for maybe two hours before replacing them in the car. then took my car for a 45 minute drive or so, trying to do a drive cycle as best I could with a few slow downs during the 45 mph portions due to traffic lights. I made sure to turn my car off and on a few times after the drive cycle. I ended it with a nice drive on the turnpike to get some solid speed in. All seemed well.

I parked for maybe ten minutes with the car off, then turned it back on to drive to the parts store. I made a slightly hard left turn with brakes applied and stalled, to my surprise, and barely made my turn with traffic headed towards me. Car started right back up and was having some hesitation, etc. and I noticed some RPM drop when I braked hard or turned steeply. I then popped the A/C back on and while sitting at a stop sign it just plain stalled. It started back up every time it stalled usually pretty easy with a pull or two on the key. Finally I got the check engine light, this was good, because I needed some codes read. After another stall or two during my drive I got my ETM light to come on.

At the shop, OBD-II codes:

P0238 TURBO SENSOR
P0236 TURBO SENSOR
P0103 MAF
P0452 EVAP
P1171 ???

So this is where I am. I have the diagnostic flow chart from XeMODeX and I am not sure if this qualifies as an intermittent problem or not now. It seems to be recreated anytime after a lengthy drive that gets up to high speed. Should I attempt to swap back to my OEM MAF or maybe attempt a ETM cleaning?

Thanks for all of your time and input.

 

After reading your post the first thing I would do is replace that relay. The fact that you said it was cracked is cause enough alone (plus the 2 black prongs). It has been noted that relay can cause the car to have some etm like symptoms. When something like a relay starts to go it can cause some parts to not get the right amount of power so you start getting pretty goofy problems sometimes. I have dealt with a failing etm before, and that doesn't sound like it is about to crap on you.

Get a new relay.

 

Do you have experience with aftermarket relays, specifically Echlin? I am able to get one on Tuesday or Wednesday and will post updates. The relay seems to be a universal relay in this car for air pump, fuel pump, starter, etc. or at least that is what their computer lists. Part R6105 at around $18-22.

 

Honestly no, but considering the price is about the same, I would just get an oem relay.

 

I went to a local junkyard and got several relays, an interior light fixture, turn signal/cruise control stalk, and intake piping for $28. What a deal for OEM used parts.

I installed the relays and the car behaves the same. Limp mode I suppose with ETS and Check Engine light activated. The car doesn't go above roughly 1,600 rpm unless floored after about 20 mph and it sounds like it is dumping boost if I do that. It won't go above about 43 mph. If I disconnect the MAF sensor the car runs very strong but shifts rough and comes off of the gas hard.

I removed the aftermarket MAF and replaced it with my original Bosch OEM MAF and the car is not in limp mode with the MAF connected anymore. It stalls after a hard acceleration to about 35 mph if I brake hard.

Another symptom that may or may not be related from my research is the fact that Cruise Control only works intermittently. With the junkyard stalk it still seems to be disfunctional but I didn't get out on the main road to really test it. The OEM would activate sometimes but the + Accel button didn't work. It would sometimes set and then deactivate from cruise control. I suspect a faulty stalk or sensor.

Does a car with a bad ETM run strong without the MAF connected? If I disconnect it, it starts a little odd from cold but settles after a one second hold of revs to about 1,500 rpm. It doesn't stall out and accelerates with full boost pressure through all the gears. I would be inclined to keep it unplugged if it didn't shift so rough and had better gas mileage.

Does an ETM exhibit these symptoms or should I try an OEM Bosch MAF replacement first? My stock MAF performs better than the aftermarket MAF that I purchased a few months ago and seemed to start failing after 50 miles or so and has become undriveable to the point of going into Limp Mode.

I never touched the contacts and only used proper cleaning solution on both of them.

 

I should amend that the car doesn't go above about 43 mph at 1,600 rpm in the highest gear it will allow. If I don't floor it, the rpms drop back down to about 900 and jump back and forth rhythmically to 1,500 to 900 ever two seconds or so, until I remove my foot from the throttle. If I floor it, which seems scary sometimes based on the sounds it makes, I can get it higher or to accelerate faster and above 1,600 rpm but the car jerks a lot so I didn't perform that very much.

Any ideas?

 

With the stock Bosch MAF the ETS light didn't appear when I started my car this morning. I'm going to clear the codes and let it run for a few days and see what pops up again. The new cruise control and turn signal stalk works nice when it actually works. The cruise control fails to set the majority of the time, but at least when it does the + Accel button works on this one.

My car doesn't drive around with the brakes illuminated, so is there anything else that would not allow cruise control to set? Turbo Pressure Sensor or maybe still a bad MAF?

That aftermarket MAF failed so fast and so badly that I wonder if they will honor a return and allow me to use the rebate towards a Bosch OEM replacement.

 

Cruise control wise no idea. I don't have any personal experience with that, thought the quickest thing to do would be to check if the vac lines are hooked up properly. It is located under the battery tray so you would have take out the battery to have a look.

Now I do want to apologize as I think it was the way you worded some of your posts that I didn't see it. You have been saying your etm light is on and you are in limp-home mode all the time? That is the ETM then. When the etm is really going on you you will have limp mode, no power practically, and WOT does next to nothing.

Now about your latest post. Sometimes your car will not start with the ETM light on(which is the ETS light) and it will drive normal. I will point out that the MAF will cause ETM like symptoms. A failing ETM will also cause your MAF to go out as well over time. From what you said, See how the car drives with that new Bosch MAF( btw, only get Bosch MAF). If you go in limp-mode again or it stalls it is the ETM. Here is a post you might find helpful in understanding things with the MAF and ETM better;

http://www.matthewsvolvosite.com/for...ic.php?t=17252

 

I will check the vacuum lines, but I am not sure that it is related or not.

The ETS light has come on maybe 5 times in the past few years, but never for an extended period of time. I recently replaced my BOSCH STOCK MAF with an aftermarket MAF that has since failed as far as I can tell. It degraded to the point of having the car enter limp-home mode while connected with the ETS light illuminated and the MAF connected. With the MAF disconnected the car would run 90% fine, but would come off of acceleration hard and would only stall if I braked VERY hard, but otherwise drove fine.

With the BOSCH STOCK MAF that came with the car from factory, I put it back in, and maybe I should have never tried to replace with with an aftermarket. It drives better than the AFTERMARKET, and doesn't seem to stall at all. The ETS light does not illuminate, and it is not in limp-home mode. Does this still sound like bad ETM? Maybe the BOSCH STOCK MAF needs to be replaced with a BOSCH MAF and not an aftermarket MAF? The BOSCH MAF doesn't seem to be perfect, but is leagues better than the aftermarket MAF which throws ETS lights and lands my car into limp-home mode.

If a MAF is disconnected, and an ETM is failed, does a car drive okay? With my MAF disconnected (BOSCH or AFTERMARKET), the car drives fine, for the most part. It just comes off of acceleration hard and has poor gas mileage.

With my STOCK BOSCH MAF the car is basically perfect again. I'll clear the codes and see if any pop up. Maybe the ones that pop up now are related to the Turbo Pressure Sensor (which may be causing the Cruise Control not to work). I will continue to update until a solution is found or until I exhaust the drive to correct this issue for those that search this in the future.

I am a DIYer and believe in building a database for more advanced technical diagnoses like these, so I am very glad that you are assisting me in this. Thanks.

 

Sounds like that was the problem. Like I said always get a Bosch MAF. If you checked out the link I gave you and what I said, a failing MAF can give off ETM like symptoms. If an ETM has failed, you will always be in limp-mode, whether it takes 1 sec after the car starts to 10 minutes. You could also check out a couple of other threads as well that I commented on because some of them were ETM problems(for your database).

Glad I could help and I hope no codes come up after you clear the already existing ones !!