View Full Version : Another 5.0 Question

07-17-2003, 10:00 PM
I take my 5.0 out about every 3 or so weeks. Whenever I start it up cold, it idles a little rough. I have to hold it at about 2 grand while I slip the clutch to get her out of the garage. I usually let her warm up at least 10 minutes before I go out for a ride. When she gets to operating temperature, no issues...idles at 800 (I guess-stock tach) with no problem at all. I know that all idle/mixture settings are dictated by the computer which is stock...so I'm wondering why the rough run.

I seem to remember hearing people talk about 'cold start injectors' causing a rough idle when cold? Anybody ever heard of that? If not or if I'm off the mark, does anybody have any advice regarding how to fix this?

Another question. I pull all maintenance on this car. In 109K miles, the only 'cheating' on my car has been rotors cut by Ford here in the states while I was stationed in Germany. I've tuned it up four times. When I say 'tuned up', I mean replace Ford Platinum plugs, air filter, fuel filer, cap, rotor, and the last time (5k mi ago) replaced wires with SVO wires I bought from Summit. If I don't use 93.5 Super Unleaded from Sunoco, I get spark knock. When I use the 93.5 from Sunoco, she runs like a scalded dog, if I don't, I can't accelerate worth a damn. Any advise?

Last question. I have used Amsoil Synthetic Engine oil since the first oil change. Amsoil recommends oil change at 25,000 miles or every year with filter change 12,500 or six months...I change it every 10K or so. When the car had 85K on it, I drove it from Washington DC to Tacoma, Washington where I was stationed. The first day I drove from DC to St Louis (80-85 mph sustained speed). When I went to check the oil the next morning in STL prior to another day's drive, it was low one quart. I topped the engine oil off and drove to Topeka, Kansas. The next day in Topeka, I had to add another quart of oil. From Topeka to Tacoma, the engine didn't use another drop of oil. About a year later, I started up my engine and heard lifters clanking (by this time, I checked the oil every week or so regularly). Checked the oil and was down a quart. Topped off and went two years without any oil loss. Moved back to DC and for a period of three weeks, put two quarts of oil in the engine. Then went six month without oil loss. Last time I experienced this anomaly was in March 2002...was driving down the road, the oil light came on. Since then, haven't lost a drop. Anybody experience/heard of anything like this?

Thanks for anything you may have.

07-26-2003, 08:51 PM
Nobody has heard of any of these conditions?

07-26-2003, 11:43 PM
The rough idle sounds like your car isn't doing the "fast idle" thing when you first crank up. It should idle fast when it is cold and then go slower when the engine warms up.

I have never heard of erratic oil consumption. Sorry :(

07-28-2003, 08:37 AM
Don't know about the idle issue.

The Cobras require the use of premium fuel. What is the timing set at? If the timing is set too high, then it will ping. Stock timeing should be 10 degrees BTDC. I run mine at 14 degrees, anything more and I get detonation. To set the timing you have to pull the spout.
The only thing I can think of about the oil consumption is the higher rpm and the oil ring is wearing out, just throwing out ideas.

08-22-2003, 07:55 PM
Originally posted by cobrapace94

The only thing I can think of about the oil consumption is the higher rpm and the oil ring is wearing out, just throwing out ideas. [/B]

So the question would be, are you seeing any exhaust smoke? And if so, is it all the time, just after you start it, on hard accelleration or decelleration?