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Discussion Starter #1
I have a 95 2.5 mpfi, it's a swapped engine and it gives me a hard time.
It vibrates at idle, I checked everything, replaced throttle body,every sensor except 02 (due for next week) and the heep still has too much advance. At idle, I have 16* of advance.

There's no vacuum leak that I could find, I have a steady vacuum of 18 until it start vibrating (engine idle goes up and down, slightly though). I tried 2 different crank sensors too. I can't remove the dizzy, the po over tighten nit and the bolt won't budge (moron).

Is there anyway for me to adjust the timing back to 8* or should I buy a new
ECU and hope for the best?
 

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Sounds to me like you need to find a way to loosen and rotate the distributor to get your base line (warm idle) advance where it needs to be.
 

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As far as I know, the timing for the 2.5L MPFI engine is set by the computer. The only thing you have to do is properly index the distributor when it is installed.

Post up the engine codes you get (codes will be stored even if the check engine light doesn't light up) and see if there is any info to be gleaned from that.

Other than that, I think I'll leave this to the 2.5L crowd.
 

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Discussion Starter #4
You are correct, on 92 and up, you can't adjust the dizzy by moving it, as it is slotted.
ECU stores no code except for AC, which I don't have. I just hope I don't have to replace the ECU after all the work I put it in the car.
 

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Check for timing chain slack, remove the dist. cap then turn the crank till the rotor starts moving then in the opposite direction till it starts moving the other way. If its more than a few degrees you have a worn timing chain set. Initial timing is fixed at the dist. adjustments for advance are made @ the ECU.
 

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Discussion Starter #6
I received a timing set last week, I intend t put it on next week after my trip to PA. I noticed a lil bit a slack on the dizzy shaft, but not sure how much is within specs.
 

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Discussion Starter #7
Found an ODB1 connector at the garage, hooked it up to the Heep and base timing is set a 14 by the ECU, goes to 12 from time to time. What bothers is it doesn't stay steady, hoovers from 12 to 16 and sometimes goes to 17-19.

I can test all the sensors with the computer, is there a chart anywhere with reading values for the sensors online?
 
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