J Sweet... where to get ECU for 92 Volvo?

Could be a shorted injector driver transistor in the ECU, that's easy to check with a multimeter if you take it apart. $800 for an ECU is ludicrous, even at an upscale junkyard it shouldn't cost more than $150, much less from a U-pull and you can swap it yourself in about 10 minutes with common hand tools. Any TV shop can check the injector driver transistor. Wish I'd known you needed an ECU last week when I was at the yard, they had a '91 and could have grabbed that for ~$30.

As long as the wrecking yard offers a 30 day exchange warranty (most do, except the pull-it-yourself yards) you are quite safe. Any ECU that works 30 days is likely to work the life of the car. I always recommend getting ECUs from wrecking yards.

Mike

Voluparts says they have a rebuilt one for 325, and it is returnable for 90% refund....this would end up costing about $55 w/shipping if it doesn't fix it. Still kind of expensive for something that is very possibly not the problem. The junk yards here (abt 5 of them) are pathetic. I don't think they are willing to warranty electrical parts for 30 days or even less. Bunch of crooks. In all the years I have had to scrounge parts, they have never had the make/model I need parts from. So I'd rather stick with some internet source. I think there is some sort of junkyard network on the internet that can locate and supply electrical parts, isn't there?

Well, I am an avionics tech, so I can check transistors or any discrete component. But the first thing I will do is put my noid light on the injectors and see if they are pulsing OK or if being held open.

What I would like to have is some inductive noid light that goes around the injector control wire to monitor the signal....do they make such an animal? I guess the pros use an inductive pickup and a scope for this, but I don't have anything like that.

regards, Geronimo

Every yard I've been to does, and I've never personally come across a bad ECU. How many $30 junkyard ECUs could you buy for one $800 new one? Do you really think you could find someone to check it for you for less than $30? This sort of thing is what junkyards are absolutely ideal for, parts that are ridiculously expensive new, cheap used, and almost always good. Why not have a spare?

Small world! I was an avionics tech (general aviation) from 1970 to 1984. It's an adventurous job at times, particularly test flights with pilots of uncertain skill level.

I would hesitate to pay the rebuilt price, if only because it's a fairly long shot that the ECU is the problem (unless it got wet while in service). Much more common are sensor problems and controller problems. The ECU can detect a dead sensor but not one that is simply wrong.

Oddly enough, many ECUs (dunno about yours) don't complain about the crank angle sensor failing. That produces symptoms like you are describing: often intermittent operation without rhyme nor reason, and complete failure when it feels like it. Now, that's something you can put your scope on! Others here are more experienced than I in that area so I will let them check in.

Mike

That $800 figure I mentioned was actually what one internet vendor is charging for an ECU---before I found the much more reasonable price of $325.00! Can you imagine the nerve? So it wouldn't have surpirsed me if a Volvo dealer wanted to charge some schmuck that much. The crooks at our local junkayrds are smart. They seem to know what an equivalent rebuilt part costs from the internet, and then charge maybe 50% less. (Or maybe its just me that they are always trying to gouge with rediculous prices.) There are also no longer any u-pull-it places....I think it is because of insurance issues. Yea, your'e probably right, its probably not an ECU. And I am thinking that its not going to be a supply power problem to the ECU as was suggested, if I find it is still showing a 1-1-1 code. If it has lost power, then it ain't gonna show any codes at all. A while back I replaced the crank pos. sensor on this car.....I seem to recall it was setting a code for it. But then I found out that the real fix was an intake hose leaking severely. SO I might go back and check that....maybe a wire to it has opened.

I am just going to go over the car for a couple of weeks, and if no joy, then get it to some garage that is more competent. I knew that mechanic was no good with electrical problems, but the brother insisted on taking it there.

Michael, sounds like you had an exciting carrer. Going up with test pilots, and all. What I do is rather boring. I work for a civil contractor which maintains a fleet of abt 50 KingAir trainer planes, which the Navy uses for multi-engine pilot training. The entire fleet is now receiving an complete avionics upgrade, from 1970s COllins analog, to the latest Collins glass cockpit with dual PFDs, TCAS and the works. So us techies are having to learn a whole new cockpit/system.

regards, Geronimo

On Sat, 10 Mar 2007 11:47:59 GMT, James Sweet wrote:

Goodness, I didn't mean to give the impression they were professional test pilots! They were just the owners, taking me up because the danged thing worked on the bench but not in the air. Most of them were good pilots, but one ran the tanks on his Apache dry over the mountains southwest of Phoenix, then switched to the reserves that were reading in the "unusable fuel" range.

Mike

;-) I'll bet you were a little white-knuckled on that one.

I have to fly with Navy pilots, but only rarely, just taking me to some airport where I have to fix a plane down for avionics. The Navy pilots have degrees and are pretty sharp, but can still be boneheads sometimes about their "switch-ology". geronimo

Roger that. I have to say that most of the techs I've known (in avionics and later in communications) who got their training in the service got it in the Navy. Another oddity - a recent "Mail Call" on the history channel took us inside Cheyenne Mountain (nerve center of NORAD) and revealed the facility was built by the Navy. Huh.

Mike

Interesting...I would have thought it was the Air Force!

Me, too, but I guess the AF doesn't get that deeply into maintenance. Dunno why, unless it's because the Navy has to handle things on its own when at sea.

Mike