Problems at WOT in 01 Lightning

[Justin07]

The truck runs great all the time except at WOT, at first i thought it was a misfire but after trying it again, it feels like the truck is bucking back and forth. I have no check engine light, if it was a bad misfire the CE light would come on, i just had that prob with my gf's mustang this weekend.
Does anyone have any idea what it could be i'd really like to get this fixed, the first time it happened i could hardly pull away from an early sn95 gt.
Seems like it might have something to do with boost or a fuel problem? i'd like to hear your ideas.
thanks,

Justin

 

[bonehead]

pull codes, if any, first.

 

[vnumus]

How many miles are on it?
I had a very similar challenge a while back.
It idled and ran great. I could nurse the throttle throughout the RPM range with little hesitation. But, when I went to WOT, it would sputter, choke, and hesitate at around 4300 RPM's.
My first thought was plugs, then fuel filter. It acted as if it were starving for fuel, but no pinging.
Your problem could be either of those, or, you could have what I had. Clogged cats.
A couple of things to look for:

From the underside, look to see if there's any seepage at the base of your heads where your headers are.

Another test is to disconnect your EGR and listen for improvement. STAY OUT OF BOOST AS THIS WILL SEND MIXED SIGNALS TO YOUR ECU.

Just "BRIEFLY" listen/feel for improvement.

Or, just remove them and check them out. I replaced mine with a Bassani mid-pipe that converts the set-up to two cats instead of four.
It'll be the head end cats that clog (usually).
If you use a "octane booster" on a regular basis, this will most likely be the culprit. Some guys actually use 2 cans of booster thinking that it could only help. Nah, it hurts more (financially) in the long run.
Clogged cats will not send you any codes untyil they're blocked 100%.

 

[TommyMac]

i had a problem like this. it turned out to be the tranny. does it shift into 2nd gear alright at WOT?

 

[Bootbox]

That's what my truck did when a couple of my coilpacks died. Have you washed your engine bay lately? Can you think of any way water could have gotten down in your plug hole area?

 

[pitstain]

cheapest to most expensive....

fuel filter
plugs
fuel pump resistor
EGR
coil packs
fuel pickups in the tank

 

[kevinatfms]

what is this fuel pump resistor??? i keep hearing about it and i have the same problem as above....i get the occasional misfire at WOT....but once in a blue moon it will sputter at idle and right during start up....i thought it might be the o2 sensors for the idle problem but at WOT i keep hearing either coil packs or the fuel pump resistors....so if someone can do a write up about it please that would be very helpful!!!!!!!!

 

[Justin07]

Thanks for the replies..
The truck has 37,000 miles on it. I havent washed under the hood so i cant see any water getting to the coil packs.
The truck shifts into 2nd no problem. I can give it hard with no problems at all, seems to be when i'm on the highway and it's at WOT pedal right to the floor that i'm getting the problem. I can boot around town , without a sputter from the truck, it runs great.
Tomorrow i'll put the scanner on there and see what it says even tho i have no CE light.
Then i guess i'll have to start going down the list starting with the cheapest thing and try some of your ideas to start eliminating things.

 

[simshahh]

is your truck stock? could possibly be spark plug blow-out if the gap is incorrect.

 

[CSHEETS]

is your truck stock? could possibly be spark plug blow-out if the gap is incorrect.

+1

 

[Justin07]

Yes it's pretty much stock other than the bassani exhaust. I didnt get a chance to look at the truck today, my mark viii blew an oil cooler line today.. figures, so i've got that to fix as well.

I'll try changing the plugs in the lightning and see if that helps any, what do you guys recommend for plugs and gap?

Justin

 

[FleeMan]

Look into some NGK plugs, have had good experience with them.

 

[beachpig]

Similar Problem

Having a similar problem.

2000 L with 30,000 miles. Mods are Borla exhaust, Volant intake. Car is shuddering real bad upon accelleration. Wont throw a cell. My friend asked me to take it on a long drive to and wait for CEL but drove over 40 miles and could not force it. It feels like a misfire on part throttle accelleration. Car idles great and otherwise drives perfect. If I get to WOT the bucking seems to go away but getting to WOT is a rough ride. My buddy put new NGK plugs in and that was not it. He then tried replacing each coil pack and that was not it. He is now going to try and replace the fuel injectors. Anyone else have any ideas. Thanks.
Gary

 

[PensiveParoxysm]

That is what my truck was doing a few days before the motor went, i pulled plugs, changed fuel filter. But still never found out what did it.

 

[beachpig]

Fixed

My mechanic friend cleaned all of the injectors and then replaced #8 coil and car is run'n great.

 

[Fast Fridge]

I have the exact same problem and its pissing me off. Apparently my exhaust stinks as well. This all happened after the last dealer injector clean so im thinking its an injector issue.

 

[KYLightning02]

Yep i have had the problem several times and every time its either the plugs or coils and sometimes both so thats what i always check when i have the sputtering problem