94 mustang trouble
 

My friend has a 94 mustang gt with the 5.0L engine. It started losing power slowly and then it got really bad. He replaced the timing chain, we checked fuel pressure which was in specs, checked the timing which is within specs, and no codes are being thrown. At the moment there is still a loss in power and at high rpms the engine sputters pretty bad. Any ideas? thanks in advance

Re: 94 mustang trouble
 

How about the ignition coil???

Re: 94 mustang trouble
 

Has he performed a static compression test or cylinder leak-down test?

Re: 94 mustang trouble
 

The spark appeared really good and strong. Could the the coil still have a problem when it shows good spark? He will be doing the compression test some time today, I had to give him my guage. We have also watched the coolant with the engine fully warmed, t-stat open, and there are no bubbles in the coolant so we dont think the head gaskets are blow. Is it possible his valve springs are weak?

Re: 94 mustang trouble
 

I threw out the coil idea because it gets worse at high rpm. Thinking at idle you get a good charge but maybe having a dying coil that doesn't deliver at high rpm. Thats a simple check with a volt meter - the specs are in the haynes manual. I figured if you had already done the timing chain, you may have done the compression check. How old are the 02's? Again, just guessing with limited info.. How many miles on the car and is it a stock 5.0?

Re: 94 mustang trouble
 

You said the fuel pressure was good. Did you check the pump for volumn??

Re: 94 mustang trouble
 

change the cam to the f303 and replace the valve train.

Re: 94 mustang trouble
 

The ignition coil is an aftermarket one, i think he said he got it from hypertech or something last year. I will check the voltage output next. The o2 sensors are good, i tested them and compared to specs. Plus it does it when the computer is cool and in open loop also. There are about 130,000 miles on the engine and it is all stock besides the cold air intake, aftermarket coil and plugwires, and a few chrome pieces here and there. How would I check pump volume? the guage only had psi

Re: 94 mustang trouble
 

i would try the stock coil, i have had a bad coil in the past that was a aftermarket go bad not long after i got it.

Re: 94 mustang trouble
 

what about teh cat. converters, they could be clogged

Re: 94 mustang trouble
 

5 month old high flow cats and catback exhaust

Re: 94 mustang trouble
 

Has the smog pump been removed? If so the cats will go bad, high flow or not.

What RPM is the noticable drop in power?

Re: 94 mustang trouble
 

down here in southern md we have no emissions testing so smog pumps cats etc dont exist. whats that??? cant help w/ that part.

Re: 94 mustang trouble
 

do you have the stock h-pipee you could try?

Re: 94 mustang trouble
 

You said you checked the timing and it was "in specs", What was it at exectly? You checked it with the spout out right?

Re: 94 mustang trouble
 

You said you checked the timing and it was "in specs", What was it at exectly? You checked it with the spout out right?