[943.8kc]

well today i started up the car and got a rude surprise that my car is missing out was fine the night before car has over 230,000 and has not been rebuilt runs gr8 above 3500 rpm but drops a cylinder or two below that any ideas exhaust smells heavily of gas can smell when standing around it i recently replaced the ccrm due to failure now this its agrrivating the **** out of me everytime i fix something something else breaks or some steals the stereo or something any ideas i hope its just time for a tune up

[Roady]

I recently purchased a 97 V6 with 99,689 miles.

I was getting a rough idle and misfire on cylinder 6 from time to time. I pulled out the Bosch sparkplugs and replaced them with Autolites, and was thinking about replacing the sparkplug wires and running a can of Sea Foam through it.

So far, with just replacing the plugs, the rough idle has gone away and it seems to be running great...still thinking about doing the wires and sea foam, but haven't got around to it yet.

I hope yours is an easy fix.

[StalkerStang]

I hate to say this, but this goes to the OP....

More then likely its the PCM. More specifically, the injector driver (transistor) in the PCM has burned out and now you have a stuck open injector, thats why when it gets above a certain rpm, it seems to smooth out.

1994 model year Mustang V6's in particular have this issue, I seem to respond to this issue at least once every few weeks.

You can verify this, using a fuel pressure guage. Engine off, put the guage on the fuel rail (shrader valve).
Turn KOEO (Key On, Engine Off), watch the guage, it should build up to around 35-40 psi, and then drop off almost instantly.
If it drops off, turn the key off, unplug all your injectors, turn KOEO again. Pressure should hold 35-40 psi. Keeping the key on, plug in each injector one at a time while watching the guage.

If an injector is stuck open due to the PCM, when you plug it in, the fuel pressure will drop.

Hope this helps

[3.8WillEatYou]

Wow, very helpful

[943.8kc]

thats sounds very possible sense i just put a new ccrm in it

[943.8kc]

did i mention it goes through 2 gallons of gas in bout ten miles

[StalkerStang]

If the injector is stuck open, it wll.

Did you try what I mention yet?