slow dropping idle

[94 cobra]

ok i just traded my 94 z28 for this 94 gt. it was a auto changed over to a 5 speed. and when driving the idle likes to hang around 2500 for a few seconds. it has CAI,and pullies i checked for vac. leak cleaned the ICM i have the screw on the ICM all the way in. from what i have read it blocks off the ICM. still a high idle could the computer from the auto be doing this?

and there is no vacume line to the FPR. where dose the line come from? and the speedometer is way off gps said 60 it said i was doing 90 do i need to just chang the gear on the trans?
thanks for the help..... maybe

[Cooter]

still have the auto ecm in it?

[94 cobra]

ya im sure it dose it has codes for some of the trans parameters

[Cooter]

I'd put a good ECM in it first and foremost

[94 cobra]

ya i think im going to try to find one out of a cobra this ecm sucks i think i have the timing at 4degrees any more and it starts to ping

[Cooter]

get an A9 (fox body) ecm

[94 cobra]

will it bolt right up? or would i have to change the wiring?

[Cooter]

I believe the pinout is the same

[sosoe]

Needs a LSx in it.

[TENGRAM]

The A9L would require more than just plugging it in.

Sounds like a hack job on the manual conversion. Need to have the VSS hooked up as well as the clutch and gear switches in order to minimize "dashpot" which is the hanging you're experiencing. You should also make sure the base idle (set with the IAC unplugged) is set below the ECM's target idle... Not sure about the 94/95s but the target idle on a manual fox is ~675 and on an auto it is slightly higher.

[94 cobra]

The A9L would require more than just plugging it in.

Sounds like a hack job on the manual conversion. Need to have the VSS hooked up as well as the clutch and gear switches in order to minimize "dashpot" which is the hanging you're experiencing. You should also make sure the base idle (set with the IAC unplugged) is set below the ECM's target idle... Not sure about the 94/95s but the target idle on a manual fox is ~675 and on an auto it is slightly higher.

i guess the VSS is hooked up it just reads real fast. i guess i need to see what gears r in it and get the right gear. the clutch switch is hooked up. i cant start the car till i push in the clutch. im not sure about the gear switch. how can i tell if its hooked up?

[TENGRAM]

i guess the VSS is hooked up it just reads real fast. i guess i need to see what gears r in it and get the right gear. the clutch switch is hooked up. i cant start the car till i push in the clutch. im not sure about the gear switch. how can i tell if its hooked up?

Should be able to start it in neutral without the clutch.

Correct me if I'm wrong, don't the 94/95s have a mechanical speedo? The VSS on foxes is only used by the ECM, not the (mechanical) speedo.

[94 cobra]

It won't start in neutral with out the clutch pushed in
Well I backed the timing back alot and it helped
Out alot but now it alot slower

[94 cobra]

ok with the timing set to 3ATDC the idle falls quick and no pinging. i set it to 10 BTDC it still hangs but picked up some power but back to hanging at 2500
anyone have a 408 i can throw in it?

[racrguy]

ok with the timing set to 3ATDC the idle falls quick and no pinging. i set it to 10 BTDC it still hangs but picked up some power but back to hanging at 2500
anyone have a 408 i can throw in it?

How about following the advice in the thread first before you go throwing another motor in it or trying to hack job a way around the problem. Auto ECU's aren't the same as the manual ECU's.