Planning On Burning The Car Soon!

[1QUICK2]

Someone please help, Jeckyl I hope you can hear my cries.

OK, for some reason my computer thinks that my car is at full throttle all of the time, making my car run extremely rich. The car will idle and sputter when the wire to the Computer from the AFM is not connected. Once the wire is connected to the computer the car dies. For some reason the car will not run with the AFM connected. I tried two diff. AFM's so its not the part that is bad. I am so sick of this car that I have decided to sell my beautiful car once its done. I hope that someone can help me or give some idea of what could be going on. Thank you for the help guys.

[JekylandHyde]

Your probelm is that you are running 500 injectors without proper fuel control. That is why you are running so rich.

You have an SAFC listed, but that is not enough to control the 550s.
At the least you need an adjustable fuel pressure regulator (www.trueleo.com/fpr.htm) so you can turn down the base-idle FP. Then you can use the SAFC to add fuel back if necessary.

I have the FPR, SAFC and VPC to control my fuel. This should all be set up with proper dyno tuning.

**side note, your signature says 350 rwhp ... the 550 injectors can not support that. They run out at 340 rwhp.

[1QUICK2]

My friend has 550's in his car with no fuel controll, and it runs/idles fine. The injectors are not the problem, it that when the MAF sensor is hooked up the car will not run. When the yellow wire to the computer in the middle harness is disconnected the car with idle but very rough. Once the wire is connected the car will die/not idle.

[scarecrowX]

have you tried pluggin in your friend's ecu to rule that out as the problem? 13 year old electronics have been known to hiccup.

check for a ground fault in that wire as well. ~0v on the afm is what the ecu interprets as full load/wot, so it's possible that the wire is shorting to ground. grab a voltmeter, unplug the ecu and check that wire for continuity to the chassis. if there is anything more than infinite resistence (meaning if the meter reads any ohm value) you have a short somewhere in that wire that you need to find and fix.

[1QUICK2]

It was reading 0 so I beleive that is the problem, hence the WOT reading. I will trace it tonight to see if it has continuity throughout the wire. I would try the ECU, but mine is a 93 and his is 91. I beleive that they are different.

[scarecrowX]

i hope it works out. good luck!

if it's diffucult to get a reading too, you can just trace that wire back to the ecu, cut it and put a jumper in line from the afm to the ecu (taking that wire out of the equation).

remember though, it's not continuity through the wire that you're concerned about, it's continuity from that wire to ground. stick one meter probe in the plug for that wire, touch the other to a clean chassis ground. if it reads 0 ohms, you've found your problem.

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So put a new wire from the AFM to the ECU or ground out the wire from the AFM to a good chassis ground? For the ohm test, do I put a probe in the AFM or ECU, and should the car be running?

[scarecrowX]

no, you shuold unplug the afm and the ecu from that wire. stick one probe on that wire, and one on a chassis ground. if there is continuity, that's your problem. there should NOT be any continuity in that wire when it's disconnected. you could try it with the ecu still plugged in as well. you are not testing anything on the afm at all.

if you want to jsut bypass that wire itself, put a jumper from that pin on the afm to the pin on the ecu where the afm plugs in (middle ECU plug, second from the right, top row while while facing the ecu)

either of those will work, but it does sound like the afm is grounding out and sending a wot signal to the ecu.