[TurboLX]

1.) Check spark plugs - This is the first thing I tell
people to do if they think they've got a problem. Pull
all your plugs out and take a look - it will be obvious
if one cylinder is having a problem.

2.) Do a leak-down test - If you think your engine is
down on horsepower a leak-down test may help you locate
the problem. It will find blown head gaskets; broken or
stuck valves; and bent or burned valves. If you're
missing a lot of power you'll need to see over 20%
leakage.

3.) Inspect oil filter - Same as your weekly
maintenance. If bearing problems are caught early by
checking the filter, you may save thousand of dollars
in repairs. A spun bearing will give little warning -
if you think there is a problem, check the filter (it
will be obvious).

4.) Check drain plug - If you're at the track and don't
have a way to inspect your filter, the next best thing
to do is check the magnetic drain plug (You do have
one, right?).

5.) Inspect valvetrain - Check the valve spring
pressure; valve lash; look for broken coils on inner or
outer springs; broken rocker arms; missing lash caps
or; broken or bent pushrods.

[toscano17]

Quite Helpful. Can a seized engine be rebuild? I've been told to just buy a shortblock instead.

[TurboLX]

a siezed engine is no good, the pistons are welded shut to the bores

[agood1]

Is the 4.6L SVT cobra motor all aluminum or are the cylinders steel sleeved?

[Nitrous Injected]

i beleve all aluminum

[LightDude]

That's a list of good tips.. Thanks..

Originally Posted by agood1 Is the 4.6L SVT cobra motor all aluminum or are the cylinders steel sleeved?

I think it's all aluminum...

[CrazyWildMike]

I build perf atv and sled engines, they all are high rpm aluminum block engines, and they all have cast or steel sleeves. I would think that if the 4.6l aluminum block had bare aluminum cylinders you would end up getting a instant bore job by the much harder cast or molly rings!

Then Again, I Have Been Wrong Before, And Likely Could Be Wrong Again!!!

...I just had to check, I pulled out my Ford Racing catalog and am looking at the Aluminum 4.6l blocks, and the "Aluminator" blocks, and I can't see any sleeves, then again, the pics aren't all that good for detail.

[black sn95]

I just bought a 91 5.0 coupe, I went out to start it up today and im getting all power when I turn the key but nothing to the starter. No click, no sound, but the the fuel pump does cut on and all dash lights work. Any ideas? Thanks!

[black sn95]

Never mind! Bad clutch switch. Thanks anyway.

[jack24panther]

Very helpful info. Thanks

[LisaWilliams]

Thanks for this information, last week i face oil filter problem and i have spend $500.
If i had got this last week, i hope I would save my $500.

--------------------------
Used Dodge Trucks for sale

[AutoXRacer]

If your engine is making nominal power, would it warrant to still perform a leak-down test...?

I am getting knock below 3,500 RPM at 3/4 to full throttle for a brief instant; the time you smash the pedal and the engine responds and begins pulling. As soon as the engine begins to pull it no longer knocks.

Its not a tuning or spark plug issue as these were already looked at.

There is a tidbit of history though. I drove the car for 28,500 miles with standard GT plugs when it should of had HT0 (one step colder). So for 28.5K miles I drove it knocking... Roush I guess forgot to change out the plugs when they built my car...

Would knocking for that long prematurely wear the engine out or cause some non-fatal mechanical failure? The engine currently makes excellent power.

Thanks for any suggestions or help...

[mp3runner1]

Very helpful info. Thanks

[Mustangluver010]

I Have A 1996 Mustang Gt Convertable 4.6l V8. I Have Been Trying To Figure Out This Missfire. I Have Replaced The Intake Manifold It Was Cracked. I Replaced Both The Coil Packs. Replaced All The Wires,plugs. I Replaced The Egr Sensor. I Replaced The Stock Manifolds One On Right Had Crack. Put New Lt Headers In With X Pipe And Flowmaster Mufflers. New Fuel Filter. NEW ALTERNATOR. I Checked All The Visable Vaccum Lines They Seem Fine. I Sprayed Brake Cleaner Around Them And The Plenium But Nothing. When Driving It Bucks When U Get On It And Pops At Idle Occasionally. When The Check Engine Light Comes On It Reads Cyclender # 1 Missfire. I Replaced Cyclender # 1 Fuel Injector Also. Could It Be Another Injector? The Car Only Has 64,000 Miles But It Did Sit In A Garage For A Long Time Unused. Thanks For Your Help

[Trick Tuners]

I have some more technical stuff i can add to the general tips listed above.
Fuel Trims are off bank to bank - Trick Tuners Forums
If you have a hanging or high idle - Trick Tuners Forums
How to find a vacuum leak - Trick Tuners Forums
How to clear the P1000 code for emissions testing - Trick Tuners Forums
Misfire and spark blow out issues explained - Trick Tuners Forums
Car stalls on clutch in - Trick Tuners Forums

[006leenstang00]

Recently I've been getting a few clouds of smoke coming out of my exhaust when I either start it up or rev it up a bit so I went to autozone and got a compression test kit and did a check on all 8 cyl's on my Cobra to see if I blew a head gasket or something. All cyl's were either 110-120psi except for cyl's 7 and 8. I checked 7 four times and got 80,85,95&100psi. I did 8 two times and got 85&80psi. Also every sparky plug end was pretty much either brown or black from oil when I took them out. The tip of the compression gauge had to be cleaned off after each cyl. was complete. The exhaust smells like terpentine too, got a little dizzy check that part of the equation lol. I don't know how long the plugs were in there b/c i'm the 3rd owner but the car has 70,125miles on it and I'm not do for a tune up anytime soon. I ran out of light and couldn't check the coolant lines for leaks but I doubt there are any leaks b/c i'd be able to smell the antifreeze burning but i'll check that tomorrow.

Do any of you guys have an idea what's going on with my engine? If it is a head gasket does anyone know where I can find a how too outline?

Any help would be greatly appreciated!