|
Hi,
You might want to take a look at this to kinda give you an idea of where you stand in the electronics arena on your car. Check out the AMM numbers to see what's up, if anything?
http://www.nuceng.ca/bill/volvo/database/ecu.htm
Having the change out of the FPR, not doing anything, doesn't surprise me.
It does help to hold the pressure consistent under all conditions.
It does vary the amount of fuel held in the rail, especially, for times of acceleration or power demand. But it doesn't make more fuel available, if it cannot get it at all.
The pressure must stay at a certain level or even go up slightly, when it varies the amount to the return line back to the fuel tank.
To be more definitive, the need of getting rid of the rich/lean conditions that could be a faulty AMM model number or a bad functioning one. That's a hard window to close, definitively, without a truly good replacement.
But the white smoke and black plugs are contrary to each other. IMHO there are too many fluctuations happening, within this self-tuning engine.
We need to get it back to some basic system functions getting right.
I remember you thought it was a vacuum leak symptomatic condition, so an intake manifold gasket would be a good start too. When cold it might be at its worse at low idle or engines speeds but never goes away! That's when I have read they are shot too pieces!
Getting a pressure reading or a fuel quantity value established, along with a compression test, to see what we are working with.
It's unlikely the injector screens are clogged, as the filters work good for a long time, but the pressure spray or cone shape has to be right.
We need to tidy things up a bit.
Finding out what was done, when and that is all we can do so far.
Like Art I'm curious to what else is different about the 1993 LH 2.4 engine.
I have one and they are a slightly different and I mean slightly different even from a 1992!
It could be as simple as the injectors that are different, especially, if it came off a 1993 with the 3.1 LH system.
It's anyone's guess and even more on my side!
I don't know if they are different, but, I know the fuel rails changed features after '88 and they added a service port, for pressure checks, that's upside down!
I'll never understand the reason to do that except to point any spray of fuel downward, for safety reasons and/or make it hard for any mechanic to fit something on there, with some cussing involved!
Did your engine keep that special rail or even get the original manifold off the1988 LH 2.2?
Hopefully, a new gasket was used, if that move was done?
Keep us posted, as this is interesting!
I Hope the link gives you insight to the changes over the years!
Phil
|
