[mif73]

Originally Posted by mif73

Hi Caprobbo.
that vid is better.
I am definately no expert with these things, but from what I can see,the maf only seems to jump around by 10mV, not sure if that is still acceptable. It also seems the maf and tp V is slightly higher than 1V at idle, they are normally just below 1V at idle.

It seems when you hold the throttle that the tpV does not alter by more than 0.2 V at nearly 3000rpm and your iac jumps up to around 50% there.
Can you switch the engine off and confirm you get a good smooth tpV from closed throttle to full throttle- about 4.5V)?
Could you do another vid also showing injector pulse width? And also confirm it is going into closed loop mode (at operating temp and running for more than 30 seconds).

If all that is acceptable then perhaps do a fuel pressure test and see if too high.
Another thing you can test with a fuel pressure gauge is an injector leak down test.
(Turn on ignition but dont crank, record max pressure then watch gauge over a minute or so to record leak rate), if pressure falls too fast you may have a leaky injector?

I made myself a pressure gauge from spare industrial machine parts - Japanese water pressure gauge that displays kgf/cm2, but I can convert that to psi well enough: )

Or buy an efi fuel pressure gauge from around 60 bucks.
Its not hard to check our engines fuel pressure as there is a schrader valve up front.

Perhaps Stu can jump in and correct me here or add more ideas.

Good luck.
Andrew.

I just checked my car.
it seems your TPV and IAC is about normal. I didnt expect the IAC to increase duty when the throttle was opened, but there you go.