Sluggish all of a sudden.

[RowdyRauder]

2004 Marauder no after market parts. 137,000 on the clock. All of a sudden feels sluggish.
No mechanical noises or codes. It feels like its pulling off in second gear (that is how slow it accelerates). From a dead stop When I hit the gas to an immediate 1/4 throttle and keep it there she pulls pretty good. But at WOT, it feels slow. Highway speedf 80 plus no problem. Also, noticed that sometimes it idles lower then it stalls. I cleaned the IAC it had little effect. Thanks guys.

[fastblackmerc]

2004 Marauder no after market parts. 137,000 on the clock. All of a sudden feels sluggish.
No mechanical noises or codes. It feels like its pulling off in second gear (that is how slow it accelerates). From a dead stop When I hit the gas to an immediate 1/4 throttle and keep it there she pulls pretty good. But at WOT, it feels slow. Highway speedf 80 plus no problem. Also, noticed that sometimes it idles lower then it stalls. I cleaned the IAC it had little effect. Thanks guys.

Check trans fluid for level, color and smell.

When was the last time you replaced fuel filter?

[RowdyRauder]

I checked the Trans fluid and it's the color of Duck sauce (like you get from a Chinese restaurant) it is a little brown. Does not smell burnt. Noticed that when it idled a little rough. The check engine light came on for a moment and went out again . Think it could be a dirty MAF?

[vkirkend]

Looks like Transmission trouble to me.

[Turbov6Bryan]

Find out what code popped up, fix that issue

Change the trans filter and top off the trans with merc 5. Should be around 5-6 quarts after you drop the trans pan and do the filter

So do you actually feel a 1-2 shift?

[RowdyRauder]

Yes, it shifts fine through all the gears. It just feels really slow down low and stumbles off the line. Thanks for all the suggestions guys.

[RubberCtyRauder]

Are you running premium fuel? Also recommend a tune when able..it wakens up the car and changes the shift schedule from constantly searching for a gear (it was made that way for the EPA gods)

[J-MAN]

Ever change the fuel filter?

[loud2004marquis]

Maybe try cleaning the MAF and air filter also?

[RowdyRauder]

Yep, running premium. I will clean the MAF and K&N this Friday. Any thoughts about it being the TPS? I plan on changing the shift points as well as you suggested. Waiting on my mechanic to get back to me.

[RubberCtyRauder]

A tune changes shifting schedule, not a Jmod or shift kit if that is what you are talking to your mechanic about

[mbmast]

Stumbles off the line? Could be the COPs. I've found that Delco COPs are just as good as Ford's and are less expensive.


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[RowdyRauder]

Thanks again guys. I plan on cleaning the mass air flow and filter today. It got warm down here in Virginia and I had to use the air conditioning and it really slow the car down a lot. The performance dropped dramatically.

[GetMeMyStogie]

Moisture under the cop covers perhaps, or weak battery, alternator, engine ground?
Whatever it is, I'd suggest solving it before masking the problem with a tune.

[RowdyRauder]

My mechanic buddy will be back in town to do a Transmission filter and fluid change. Is the filter for a 2004 MM FT-105? I will be adding a drain plug too. Thanks guys

[RowdyRauder]

Update. I changed the trans filter and fluid and fuel filter. Transmission shifts smoother. But....
1. Still lacking power.
2. Still idles irraticaly at times.
3. Stalls at times going into corners
4. Noticeable loss in power when either the a/c or heat is on.
5. Loss of MPG. (Filled tank went 130 miles highway/town traffic) now at half tank.
6.No codes on cpu

[1Marauder]

Also, have you touched or rotated tires lately? I know... Dumb question, but gotta ask.

If it came on suddenly, without touching the car at all... Look for air leaks in CAI or maybe fuel pump?

[RowdyRauder]

Yes, I changed the tires to run the same size all the way around. I keep the traction control switch off to prevent it from activating since the tires are no longer staggered. The tires were changed last summer

[tobiasg1995]

Have you changed the fuel filter yet?

2006 GMQ, 2010 CVPI

[RowdyRauder]

Yep. New fuel filter two months ago. Also, I don't have a cold air induction. Anyone think it could be a faulty TPS or Faulty mass air flow sensor?

[Turbov6Bryan]

I wonder if your catalytic converters are some what clogging up

Does the engine rev up redline in park or neutral?

[RowdyRauder]

Thank you Turbo V6. What is normal when you rev it park or neutral?

[Pat]

You still have not changed the COPS. Do it and do it now, you can thank me later. If you want buy a cheap COP and walk it thru the cylinders and see which one (s) respond.

I had the same problem and lived with it for a year, no CEL's.l I took it to a small repair shop and he solved the problem buy buying one COP himself, he found three bad COPs before he gave up and sent me to the parts store. No more problem, instant fix.

BTW change all eight.

[RowdyRauder]

OK. I'll change the COPs. I just tried to bring it up to red line in park. But it started to act like it was hitting the rev limiter at 5,000 rpms. Any advice on changing the COPs? Any special tools needed.

[fastblackmerc]

OK. I'll change the COPs. I just tried to bring it up to red line in park. But it started to act like it was hitting the rev limiter at 5,000 rpms. Any advice on changing the COPs? Any special tools needed.

If you can change spark plugs you can change the COPS. Just be careful taking the connectors off. Use a small amount of silicone dielectric grease in the boot when replacing.

[Turbov6Bryan]

If the engine is not missing out and won't rev past 5k I would suspect the cats are clogged up

What issues have you had with the engine in the past?

Does your engine have a miss?

[RowdyRauder]

It doesn't have a miss. No back fire. It revs up to 5,000 before it starts to sound like its hitting the red limiter. I'll see if I can get an audio of it .And attach it.

[Turbov6Bryan]

Make a YouTube vid with your phone if possible, show us the engine and how good or bad it's running

Then let's hear the exhaust

[1Marauder]

Agree with above, Also check fuel delivery.

[Davco]

Any updates? I'm having a similar issue with lack of power and erratic idle. I cleaned the IAC and MAF and TB but not much change. I am researching plugs and COP now (119k on the clock).

[JustRight]

Just a guess here, but sudden changes are often related to a recently pumped, poor tank of fuel. Happens so very often around here.