Misfiring

simon clemens · 10-12-2005, 07:18 AM

Hi all, I need help to find out some info with my 1995 mustang engine, (stock standard, curved intake neck). Firstly need to know what the IAC (Idol Air Control) screw looks like. I know where it is supposed to be... as I have removed the grey rubber plug on the throttle body and there is just a hole with a thread inside.... NO adjustment screw in there at all!! I was told by the guy who tuned the engine that "maybe it came loose in the throttle body and was sucked into the intake" this sounds to me like a whole lot of BULL SH!T, however I am led to ask the question is this possible?.
I need to know because the engine now has a misfire on number 2 cyl. The engine had just been dyno'd by this guy and he said that is was running perfectly fine on the dyno. Now I have a missing number 2 cyl, and he is claiming it is not his problem. He performed a leak-down test and discovered air leaking back into the intake... which indicates the intake valve is not seating.
Symptoms when running:
-Cold exhaust temp on number 2cyl
-Can easily hear the misfire on the right bank (twin exhaust system)
-good fuel inj, spark/leads, dizzy cap, coil

What could have caused my engine to now be running on 7 cylinders??? The day I picked the car up there was this problem with it.

Is it possible that the IAC screw has gone through the engine and damaged the intake on number 2cyl?

Please... any help on this will be appreciated, Simmo

10-12-2005, 07:18 AM	#1
simon clemens Registered Member Join Date: Oct 2005 Posts: 3	Misfiring Hi all, I need help to find out some info with my 1995 mustang engine, (stock standard, curved intake neck). Firstly need to know what the IAC (Idol Air Control) screw looks like. I know where it is supposed to be... as I have removed the grey rubber plug on the throttle body and there is just a hole with a thread inside.... NO adjustment screw in there at all!! I was told by the guy who tuned the engine that "maybe it came loose in the throttle body and was sucked into the intake" this sounds to me like a whole lot of BULL SH!T, however I am led to ask the question is this possible?. I need to know because the engine now has a misfire on number 2 cyl. The engine had just been dyno'd by this guy and he said that is was running perfectly fine on the dyno. Now I have a missing number 2 cyl, and he is claiming it is not his problem. He performed a leak-down test and discovered air leaking back into the intake... which indicates the intake valve is not seating. Symptoms when running: -Cold exhaust temp on number 2cyl -Can easily hear the misfire on the right bank (twin exhaust system) -good fuel inj, spark/leads, dizzy cap, coil What could have caused my engine to now be running on 7 cylinders??? The day I picked the car up there was this problem with it. Is it possible that the IAC screw has gone through the engine and damaged the intake on number 2cyl? Please... any help on this will be appreciated, Simmo Last edited by simon clemens; 10-12-2005 at 08:28 AM..