Quote:
Originally Posted by werminghausen
Set dwell at 30 degrees, Ignition timing at about 3 degrees ATDC (w/vacuum) about 8/9 degrees BTDC (w/o vacuum)..vacuum at 13" (w/vacuum) and 17" (w/o vacuum).
Idles poorly in a way...set pressure at 32psi...drives poorly. Not much power.
I measured AFR 17.4 on the way coasting, 13 at acceleration and 24 at idle...
How can this engine be so lean?
Didn't touch MAP sensor.
I was guessing that AFR is too rich but it is the opposite?
What is wrong?
Is this the reason the engine performed poorly?
Need help
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Those lean readings could be due to the sensor location. Try the rag trick and see if they go up, especially at idle. It could be you are measuring a mix of exhaust and outside air.
If the figures are right, fuel is just not getting to the engine or through the injectors. Forget MPS for moment.
At idle, the MPS has no function if the TPS is set up properly. Make sure that is set properly (see link upthread), then set ECU knob in center (11clicks either way?) and turn it each way one or two clicks at a time and see how AFR changes. Give engine a short burst in-between settings and give it a few minutes to settle down. Try to get to about 4% CO (13AFR) at idle with engine warmed up.
If mixture remains lean even with rag in one tailpipe, then maybe you have another problem. But maybe relocate bung first!
Then, I would check fuel delivery rate downstream of fuel pressure regulator. You should have 1L/30sec flow. You can measure this by connecting a hose to FPR or damper outlet and either jumpering Fuel pump relay or power fuel pump directly from battery (need a friend to help!). There is also a method in manual for checking individual injector fuel flows. (
also in this link, along with much more!)
One other thing - do try and confirm that you are getting centrifugal advance (even if you don't know what rpm are exactly) Rev engine hard and you should see advance go up to 30deg+ BTDC.