laging at 40 mph

[g_htwoo]

hi u all.. i am having problems with my 03' marauder. when i accelerate it starts to lag and idles rough at about 40 to 50 mph. what could be my problem? oh and i already replace the IAC valve.

[musclemerc]

You need to provide more information. It's kinda hard for any vehicle to idle @40~50mph...

[g_htwoo]

Well it drives normal till i hit 40 mph Then it jus starts to sputter & lag till i get ovr 60 mph. It shut off on me three times while idling at a stop light. I thought it was my gas but it wasnt. So i look on this page & it post something about a bad or dirty iac valve. So i replaced with a factory new one but no luck.

[ntd]

Off the wall guess as there isn't much info and I haven't seen the car in person. A bad coil on plug usually causes a sputter on light acceleration. As for the stalling at idle perhaps a vacuum leak. Need more info any codes, mods, did this problem just start or something that has gotten worse over time. Perhaps you should introduce yourself and fill out you profile:dunno:

[MercOut]

Off the wall guess as there isn't much info and I haven't seen the car in person. A bad coil on plug usually causes a sputter on light acceleration. As for the stalling at idle perhaps a vacuum leak. Need more info any codes, mods, did this problem just start or something that has gotten worse over time. Perhaps you should introduce yourself and fill out you profile:dunno:

I think i have this sputter at 40mph also. So i need new coils?

[TooManyFords]

Clogged fuel filter.

[musclemerc]

+1 try the fuel filter first if it continues the replace the coils.

[ntd]

I think i have this sputter at 40mph also. So i need new coils?

only true way to know is to load test the coils

[MercOut]

Clogged fuel filter.


+1 try the fuel filter first if it continues the replace the coils.

I really haven't noticed the stutter in a while but I'll check this weekend.
When you say try the fuel filter, do you mean replace it? It's only $10 at autozone



only true way to know is to load test the coils

I don't know what load test the coils mean. Could you explain?

[musclemerc]

Replace the fuel filter if the sputter continue's replace the coils. If you do need coils MDRider88 shoot me a PM. I can get you a deal.

[CBT]

Replace the fuel filter if the sputter continue's replace the coils. If you do need coils MDRider88 shoot me a PM. I can get you a deal.
I will second that :beer:

[MercOut]

Replace the fuel filter if the sputter continue's replace the coils. If you do need coils MDRider88 shoot me a PM. I can get you a deal.

Will do! you tha man:banana:lol

Havent forgotten about the pics of the EGR either. just haven't had time

[ntd]

I don't know what load test the coils mean. Could you explain?

It's testing the capability of the coils to create the spark under high load. Testing is done with and oscilloscope and an inducting pickup sensor. Nothing the normal person would have but any shop that does driveability work should be able to perform the test.

[g_htwoo]

well today the check engine light came on. i took it to autozone and it read bank 1 and 2 too lean. ill try the fuel filter too tomorrow. hey bro what kinda deal u got on coils? how hard is it to replace the coils? could a bad MAF or throttle position sensor be the problem?

[g_htwoo]

Replace the fuel filter if the sputter continue's replace the coils. If you do need coils MDRider88 shoot me a PM. I can get you a deal.
what kinda deal you got on coils?

[musclemerc]

if both banks are lean then its a vacum leak.Check the line that runs from the PCV valve to the upper intake. Its notorious for cracking.

[jus2rel]

I have been wanting to replace my coils and COP connectors for a while now, but I am not sure what brand, type and price range I should be looking at. My marauder is stock so nothing too fancy.

If anyone can give me a brand and type I need, along with a price range and where to buy them, I would greatly appreciate it.

[whitey]

i think i have the same problem with my marauder, but at 40-60 under a light throttle. i replaced the fuel filter, and the spark plugs...didn't fix it(however the new fuel filter seemed to help with acceleration a whole lot). drained the tranny fluid..like 4-5 quarts like 3 times, and its still doing it. good luck on finding the problem, it might be that i have the same--whitey

[whitey]

fixed it, had a misfire in one or more of my cylinders, changed out the cop's, runs perfect.

[whitey]

accidental post....

[JET]

spark plugs