Losing Power during accel at 3k+
08-06-2008, 06:52 PM
#1
Thread Starter
Join Date: Mar 2003
Location: Nebraska
Posts: 10
Losing Power during accel at 3k+
Hi guys,
I just recently noticed that my car is losing power from around 3000 all the way to 6000 rpm during acceleration. I noticed it during a 200 mile drive home last week, and couldn't figure out what it could be.
Background:
2005 Mustang GT
JBA LongTubes, Offroad H, Mufflers
Steeda CAI, Xcal2 tune from Kauffman of Pennsylvania for 93oct
I live in Nebraska and it's tough to find 93 Octane out here, and in the meantime I've been putting 91oct in it and adding an octane booster (Octane Boost 104 or something) and it's been doing just fine. Before I started the trip I stopped at a gas-station that has 93 octane and topped it off, it had about 10 gallons of 91/104booster and then topped off the other 5.5ish with 93. The last time I drove it before that I had replaced the sparkplugs.
Symptoms: Losing power at 3k+ rpm, only from 3rd gear through 5th gear, sometimes in second I'll notice it start at 5k. It's not only losing power, but every now and then I can hear it igniting in the headers as well. It feels like a timing issue, but I'm not exactly sure. I recently replaced the plugs and it was fine for the 200 mile drive to my buddies house, but on the way back it started losing power. Also just did the Fuel filter today, and still exhibiting the same problems. Using 5w-20 synthetic with a fram extreme guard oil filter (if that's helpful)
It's hard to describe the feeling. It's like you feel it start to pull but then the gas is just dropping off and then kicking in again randomly, almost like it's not getting any fuel. I checked all of the plugs again today, and they look ok.
I should also add, when sitting in neutral it will rev up to 6k without any hesitation or backfiring.
Any help would be great!
-Canton
I just recently noticed that my car is losing power from around 3000 all the way to 6000 rpm during acceleration. I noticed it during a 200 mile drive home last week, and couldn't figure out what it could be.
Background:
2005 Mustang GT
JBA LongTubes, Offroad H, Mufflers
Steeda CAI, Xcal2 tune from Kauffman of Pennsylvania for 93oct
I live in Nebraska and it's tough to find 93 Octane out here, and in the meantime I've been putting 91oct in it and adding an octane booster (Octane Boost 104 or something) and it's been doing just fine. Before I started the trip I stopped at a gas-station that has 93 octane and topped it off, it had about 10 gallons of 91/104booster and then topped off the other 5.5ish with 93. The last time I drove it before that I had replaced the sparkplugs.
Symptoms: Losing power at 3k+ rpm, only from 3rd gear through 5th gear, sometimes in second I'll notice it start at 5k. It's not only losing power, but every now and then I can hear it igniting in the headers as well. It feels like a timing issue, but I'm not exactly sure. I recently replaced the plugs and it was fine for the 200 mile drive to my buddies house, but on the way back it started losing power. Also just did the Fuel filter today, and still exhibiting the same problems. Using 5w-20 synthetic with a fram extreme guard oil filter (if that's helpful)
It's hard to describe the feeling. It's like you feel it start to pull but then the gas is just dropping off and then kicking in again randomly, almost like it's not getting any fuel. I checked all of the plugs again today, and they look ok.
I should also add, when sitting in neutral it will rev up to 6k without any hesitation or backfiring.
Any help would be great!
-Canton
08-06-2008, 08:13 PM
#4
1st Gear Member
Join Date: May 2006
Location:
Posts: 145
RE: Losing Power during accel at 3k+
No SES light on yet?This sounds alot like problems with the runners sticking closed(charge motion plates),And they open up at around 3k,But that would throw a DTC usally.Im not 100% but thats what what it sounds like.Ive seen a few at work with these things sticking and they are DOGS.And get rid of that fram filter[:'(]No good!Let us know what you find.
08-06-2008, 10:53 PM
#5
Thread Starter
Join Date: Mar 2003
Location: Nebraska
Posts: 10
RE: Losing Power during accel at 3k+
Had my dad rev it up in neutral while watching the charge plate linkage, they were moving properly. Is it possible for the plates to be stuck shut even though the linkage moves? Also, what would you recommend in place of the fram? Just a motorcraft? One final question, I read in another thread that a guy was having trouble with his alternator, and that the 05/06 alternators had a tendency to fail, any truth behind this, or am I in left field?
-Canton
-Canton
08-07-2008, 09:50 AM
#6
3rd Gear Member
Join Date: Feb 2008
Location: Nebraska
Posts: 794
RE: Losing Power during accel at 3k+
First off - it is good to see another member from Nebraska on here! I am located just south of Omaha. Secondly, I have heard not to use octane booster in these cars. If I remember right it has something to do with fouling plugs and or clogging fuel injectors. I would look into getting a different tune for 91 octane since that is what most the pumps around here have. I'm not even sure where you found 93 octane because I have never seen it.
Regarding the alternators I don't believe this was a problem in a lot of cars. Rather it was the batteries. Often when the battery goes bad people were mistaking it for the alternator.
Regarding the alternators I don't believe this was a problem in a lot of cars. Rather it was the batteries. Often when the battery goes bad people were mistaking it for the alternator.
08-07-2008, 11:05 AM
#7
Thread Starter
Join Date: Mar 2003
Location: Nebraska
Posts: 10
RE: Losing Power during accel at 3k+
Yeah I'm thinking I might hit up brenspeed for a set of tunes. The 93 octane was in Bellevue at a Phillips 66 station. I dropped it back to factory tune this morning, going to try and reprogram it again in a bit, just getting frustrated with the loss of power.
So the difference between the factory and the tune was noticeable, but it's still exhibiting the same symptoms from earlier. Gonna go pick up a bottle of injector cleaner and give brenspeed a call.
So the difference between the factory and the tune was noticeable, but it's still exhibiting the same symptoms from earlier. Gonna go pick up a bottle of injector cleaner and give brenspeed a call.
08-08-2008, 12:59 PM
#8
Thread Starter
Join Date: Mar 2003
Location: Nebraska
Posts: 10
RE: Losing Power during accel at 3k+
Ok, this is really starting to irritate me. It's almost irrational. I can't think of anything that would pin down what's happening. Today I drove back to Omaha from Grand Island (appx 200miles) and as long as I'm just cruising it's fine, but as soon as I give it gas it starts to stutter and then finally backfires a few times, slowly increasing speed. I've found it's different for each gear, which is even more confusing. In first it's not noticable at all, in 2nd only from about 4500+ rpm, 3rd it starts around 3500 rpm, then 4th and 5th it's the entire rpm range. It's driving me up the wall at this point. Would this have anything to do with the variable cam? I don't want to take it to a shop but my options are getting pretty slim here. Thanks,
-Canton
-Canton
08-08-2008, 10:30 PM
#9
1st Gear Member
Join Date: May 2006
Location:
Posts: 145
RE: Losing Power during accel at 3k+
Maybe you have a bad tune?Its hard to do an actual diag over the internet
I would for sure call brenspeed and get some of there tunes.It could be a few things though,have you ever replaced the fuel filter?Maybe your fuel pumps going south.As far as an oil filter,motorcraft FL-820.3v's are picky on oil filters.If you have no SES on,I would say its in your tune.It could have something to do with the VCT but usally you will throw a DTC,and if you had a phaser going out,you would know it.Let us know.
I would for sure call brenspeed and get some of there tunes.It could be a few things though,have you ever replaced the fuel filter?Maybe your fuel pumps going south.As far as an oil filter,motorcraft FL-820.3v's are picky on oil filters.If you have no SES on,I would say its in your tune.It could have something to do with the VCT but usally you will throw a DTC,and if you had a phaser going out,you would know it.Let us know.
08-08-2008, 10:47 PM
#10
Thread Starter
Join Date: Mar 2003
Location: Nebraska
Posts: 10
RE: Losing Power during accel at 3k+
Yeah I actually just replaced the fuel filter this past Wednesday, if the 3v's are in fact picky over the oil filters I'll change that up next week and get a motorcraft part in. The best thing I can come up with is the gas I put in when it started is the culprit, but then it -should- have cleared up by now. Also I've had that same tune on there since October-ish of '05 with no other problems. I did however just change regions from East Coast to Central, so maybe it's the humidity or something. I have an X3 with the three tunes on the way from Brenspeed, got that going already. Just getting a sick feeling, the car is my baby, and with it not working properly it's driving me bonkers. Like I said earlier, no codes being thrown, except a P0506 (Lower than expected idle) after I reflashed the tune. Hoping it's not the fuel pump, but with all of the octane booster junk I've been putting in it I guess I shouldn't be too surprised. Last but not least, today I was just curious if it would throw a code, like I had said earlier, it tries and stutters a bunch then starts to backfire, well, today it started flashing the CEL but after hooking up the tuner it couldn't find any DTCs. Weird. Anyway, thanks for the advice turbotbirdguy79.