Mystery car-2004 rebuilt engine, car ran for 2 days-won't run

I had '04 Isuzu Rodeo engine rebuilt. It ran for 2 days then stopped. The mechanic found a loose wire which apparently shorted the ECU. He tried a used replacement, with no luck. I had the ECU rebuilt by a specialty shop. It still wouldn’t start. For over a year several mechanics, including at a dealership, have had no luck finding a problem. The mechanic found another shop which thought they could fix it and he paid them $1500.00 to replace the fuel filter(in the gas tank I guess?). Still it’s a no go. Any ideas?

We need more info:

What happens when you turn the key to try to start it? Does it turn over but not start? Does it do nothing? Does it start and then dies right away?

To run, an internal combustion engine needs: Fuel, air, and spark. Depending on the specific setup of your vehicle- some of these are controlled by the ECM/ECU, some are just monitored by the EC/ECUM. Check for which one you don’t have and go from there.

It is possible that if the ECU got shorted out, that something else may have been sorted as well.

I think OP needs to bring the truck to a different shop

These jokers are clearly incompetent, if they’ve had it for over a year, and haven’t figured it out yet

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First confirm a visual test for spark at the spark plugs during cranking. If the spark is there ok during cranking, spray some starter fluid into the throttle body and see if it will start briefly. Report back what you find. Cranks ok but doesnt’ start is usually a fairly simple thing to diagnose. Fixing it may not be so simple. But to have any chance of getting this resolved you have to determine what basic function is not working & causing it not to crank ok, but not pop and start.

Yeah, he’s very good on some things but this is out of his area of knowledge. For this reason he has taken it to at least four other shops who are supposed to be specialists. Twice to dealerships and a time or two to specialty shops. The last one charged him (out of his own pocket) $1500.00 to r&r the fuel pump (in the gas tank-so stupid). One reason he’s had it so long is that I moved to another town-also he got money up front for the rebuild and is to take my other car in trade for the this one (still in his name).

Thanks I’ll check on that.

Thanks I’ll check on that. This mechanic is very good on most things but this is outside his area of expertise. He has taken the car to at least four other shops–two dealerships and two specialty shops. One of them changed the fuel pump (in the gas tank I guess-he paid $1500.00 out of his own pocket). If something else was shorted what do you think it might be? This is difficult for me since I’ve moved to another town, so I’m doing this long distance.

True. But it also needs compression. Chances are that the spark or fuel is missing, or the ECU doesn’t know the engine is cold, but if… just if… something was (not) done in the rebuild that allowed the valve timing to go out, that could also cause a dead engine. It’s a longshot, but I wanted to throw it in the list so it doesn’t get overlooked.

Db is, IMHO, totally correct, this needs a new shop to look at it. It should not take a year to diagnose a nonstart condition, whatever it is.

OK, thanks. I’ll check into that. Just to try and get a fuller picture out to you all- I’ll add this information— this is a 2004 Isuzu Rodeo. Apparently it was different from all of it’s predecessors, and was the last year made. After rebuilding the engine, the car ran for two days. When it stopped, it was determined that a loose wire caused the ECU to short out. I had the ECU rebuilt at a shop in Colorado. Since then the car has been taken to at least four different shops including dealerships. Thanks for all your ideas–I’m hoping that someone will have found a solution in a similar case.

Each no start condition like this is usually different. We don’t know anything about the results of the diagnostic process used so there is no way of knowing where the problem might be found. When people replace the computer (guess work) there is usually a problem with an input to or output from the computer, most computers are replaced in error. There is a “no start” diagnostic process in the service manual. It is a matter of biting the bullet and testing each wire and sensor in the instructed circuits until the problem is found, typically this can be done before lunch by the right technician.

I know you are right about this. Unfortunately I’m a couple of hundred miles away from the car and my mechanic’s primary language is not English. Be that as it may, he has found what he believes to be the problem. He says that the car is now running but it has “fried” several starter coils. He believes this to be because of the ECU. He’s sending it back to me so I can return it to the company who rebuilt it as it is under warranty. I’m wondering if the problem could be the Ignition Control Module. I would be interested to hear any new thoughts you might have on this. My mechanic is insistent that the problem is in the ECU only. Thanks for your input.