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Hi all,
New to this site...hope your combined expierience can help resolve my problem. First, this is a 94 firebird engine, trans & rear end transplanted into a 66 mgb. It starts immediately but idles rough. Has a definite flat spot then runs great. This what I have checked;
TPS- tested with multimeter. Ignition on only, steady voltage increase from 1.2 to 4.5 as throttle is opened. Engine running 1.2 to 2.5 +-
IAC- tested with multimeter. Correct resistance.
MAP-tested with multimeter & vacum pump. Checks out.
Cam & crank sensors- tested for continuity and voltage only.
Coils & ICM- tested with in line spark tester. Good spark all cylinders, plugs all look good.
Compression- 180 all cylinders.
Fuel pressure- 42 ign on not running. 38 running at idle. Pressure drops right away when ign. is off but remains static if fuel delivery line is pinched off. Check valve is bad at pump but this shouldn't be the problem??
The tach (Speedhut) doesn't work. The tach wire at the ICM shows no voltage at any speed. When I checked it out I found that it has continuity to ground!! What should the voltage be, or what is the correct test? Could this be related to the problem?
Thanks
New to this site...hope your combined expierience can help resolve my problem. First, this is a 94 firebird engine, trans & rear end transplanted into a 66 mgb. It starts immediately but idles rough. Has a definite flat spot then runs great. This what I have checked;
TPS- tested with multimeter. Ignition on only, steady voltage increase from 1.2 to 4.5 as throttle is opened. Engine running 1.2 to 2.5 +-
IAC- tested with multimeter. Correct resistance.
MAP-tested with multimeter & vacum pump. Checks out.
Cam & crank sensors- tested for continuity and voltage only.
Coils & ICM- tested with in line spark tester. Good spark all cylinders, plugs all look good.
Compression- 180 all cylinders.
Fuel pressure- 42 ign on not running. 38 running at idle. Pressure drops right away when ign. is off but remains static if fuel delivery line is pinched off. Check valve is bad at pump but this shouldn't be the problem??
The tach (Speedhut) doesn't work. The tach wire at the ICM shows no voltage at any speed. When I checked it out I found that it has continuity to ground!! What should the voltage be, or what is the correct test? Could this be related to the problem?
Thanks