Hey guys, I got another one. All I did was put some BBK shorties and a cat-less x-pipe on (taking off my stock y-pipe) -- I did also put new titanium spark plugs in it and I did disconnect the smog pump. Both o2 sensors are hooked up and it's not throwing any codes. The performance is terrible and the gas mileage is suffering. It shudders on any but the lightest acceleration. As soon as the engine cools off I'm going to check to make sure all the boots are on the spark plugs properly but I can't think of anything else that might be wrong. Anyone have any ideas?
Sounds like ignition issue. Better put some regular everyday cheap plugs in it. Those designer plugs are not what they are cracked up to be. Sounds like one is bad!!! Or a plug wire is arcing on the headers.
I would recheck the plug wires first to make sure you didn't get some crossed. Next I would check the timing and make sure its set properly. If that isn't it I would check to make sure you didn't crack a plug.
Totally ignition. Ignition misfires kick back hard, fuel misfires, not so much. If it's on accel, I'd expect you to be leaking spark to ground someplace. Check that you didn't get a plug wire up against those new headers. And like Tom said, get some regular plugs. Those specialty plugs wreak havoc on an old motor like yours. You'll find that just about any recessed electrode plug will run like ass, and your best bet is a set of resistor core Motorcraft plugs or resistor core Autolites (in my experience).
Yep get those plugs out of there. Try a set of copper core Motorcraft plugs instead. That's what the ignition system was designed for.
Also you did out the plug wires in the 1-5-4-2-6-3-7-8 firing order correct? That's the firing order for a 5.0 SO. The 1-3-7-2-6-5-4-8 firing order is for the 5.0 HO/351W.
You guys rock. I pulled all the titanium plugs out and replaced with regular autolites. Problem solved! I spent a lot on those titanium plugs -- now they are paper weights. Thanks again!
You guys rock. I pulled all the titanium plugs out and replaced with regular autolites. Problem solved! I spent a lot on those titanium plugs -- now they are paper weights. Thanks again!
I know a lot of people think i am a DICK on this site because i tell it as it is but we have had so much trouble with those designer plugs it is unreal. We never use them in our cars only as replacement on OE Equipped vehicles. We have seen this time and time again. people think they can redesign the wheel but it aint happening. The minute you said you used those plugs me and junior just looked at ourselves and chuckled. Not because we look down on it just because we knew instantly it was the issue. With plugs we have found you can not beat the regular tried and true copper old fashioned ones. By the way we use NGK with very good results over all other plugs we have tried. They make a dam good plug and we have had no issues with them. I may not be perfect but i am as close as you are going to get. just kidding glad you fixed the issue. Bring those plugs back for a refund.
When I was 16 in my auto tech class, a kid bought some 4 pointed titanium plugs. went to fire it up and it barely ran. pulled them back out and one of the tips had broken off in the week they were in there. since I saw that, I run the $1.80 motorcraft coppers. used to be a dollar a piece.
TRUE STACKS there is just some things that can not be improved on. And the old fashioned plugs work just fine for me. TRUE STATEMENT STACKS i have actually see that happen from time to time. Someone is always trying to mess up a perfectly good product with gimmicks.
On the other hand, some engines run really great with them, just nothing that came in a Fox Thunderbird.
It was a corolla or civic or something in my auto shop class. something small with an ohc and only a year or two old.
I agree with Tom, tell them the associate recommended those, didn't work correctly, and take em back
I had to buy some of those ngk platinums or whatever they are for my wife's car and wow they were expensive
I'm so glad the plugs for my cars are dirt cheap in comparison
True that is why we use OE plugs when they are designed for them. But the LS motors do run great with copper plugs!! Late model cars that are designed for them naturally run correctly. Years back we got many service bulletins on using the wrong plugs on Toyota and nissan engines. If you used the wrong plugs it fried the coil packs. Ask me how i know!!