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Just put a change over MPFI EA82 into my touring wagon, as the old one has a head gasket or crack problem and overheats.

This one has one final niggle, under hard acceleration it feels like it runs out of juice, feels kinda like when the rev limiter kicks in, and at idle it runs rough and sometimes stops, usually when the lights go green.

I've checked and adjusted timing etc, replaced leads, had a stuck thermostat causing it to idle to high via the air bypass valve.

At first I thought fuel filter, but that was in the car with other engine and it didn't have the same problem, so it would have to be coincidence.

So I'm thinking fuel pressure regulator, any one had any experience with these failing?

Or any other ideas??

A main offender to probs I found with these symptoms, is vacuum leaks. Also give the airflow meter a clean, especially if its a hotwire type, with electronic cleaning fluid. The next thing would be to give the tank a dose of injector cleaner. Hope this helps.
Roger

Thanks Roger,

The airflow meter wasn't changed in the engine swap, but I might do it just in-case, I'll have a look for vacuum leaks, cause that kinda makes sense, it feels like it is intermittently getting to much air or not enough fuel, I put some injector cleaner in last night, so I'll see if that sorts anything out.

Cheers

I was thinking injectors need a clean like subantor was getting at. If the injector clean doesn't change anything, try swapping the injectors from your other engine and see if it makes a difference (if you can't find anyother thing that is causing this).

Subies are notorious for vacuum leaks, always a good start to check these out, it's relatively easy to do too.

Cheers

try checking the altinator voltage, My 82t converted brumby had suffered the same symptoms. Turned out the voltage was dropping off at revs. It felt like it was starving from fuel under load, and acted like a vacum leak at idle. Unfortunately it failed while at peake. Made for an interesting trip home.

Finally had a chance to spend an arvo fault finding, I checked for vacuum leaks, but couldn't find any, then I thought what's the easiest thing to swap from the old engine to the new one? The dissy, and I struck it lucky, that was the problem.

Maybe someone can shed some light on what might have been the issue with the distributor, it's an electronic one, as found on the MPFI.

Cheers for the suggestions.

What year MPFi motor? If it is later than mid 87 (ie. 4 plug ecu, optical vane disty) ,.. there is nothing inside the disty that can be serviced so if it is broken, i dont think ya have much chance of saving it. Try the wreckers

Pre 87 you might have a chance as i think the disty was similar to the carb'd versions and has a few servicable parts inside. Also better chance of finding one at the wreckers.

So does your car work properly now?

If its the optical one it could be something simple as a piece of dust in there.