Problem at WOT

[SaleenCobraSwap]

I am having an issue with my 03 Cobra, Its like when I crush the throttle it seems to start cutting out. Its actually a really difficult problem to describe, it acts as if it isn't getting enough fuel, but it doesn't seem like it just happens at high RPM. IE: If I crush it at 40 in 6th gear it still does the same cut-out thing as it does at 5k or 6k. I also just noticed that it seems to make my aftermarket oil pressure gauge go nuts (Bouncing from like 50psi - 150psi instantly even when i get out of the throttle. I have had the car for about a month and it has had the problem since I purchased it, but the car honestly makes enough power that I've hardly needed to come all the way into the throttle. After noticing the oil pressure gauge I will not be driving it until I have solved this problem. I realize that this is a crappy explanation, but if anyone has any ideas, I'd really appreciate it.

 

[SaleenCobraSwap]

I also forgot to Mention engine setup. According to the previous owner: 2.73 Pulley, Stage 5 port, full exhaust, tuned at 14lbs of boost. I initially thought the supercharger belt could be slipping, but after the oil gauge freak-out, maybe not.

 

[02blownGT]

TPS possibly?Its hard to diagnose without seeing the car in person.It could be the tune or fuel delivery as well but the TPS is an easy place to start. Goodluck

 

[SaleenCobraSwap]

TPS possibly?Its hard to diagnose with seeing the car in person.It could be the tune or fuel delivery as well but the TPS is an easy place to start. Goodluck

Wouldn't the throttle positioning sensor throw a code?

 

[02blownGT]

It could but sometimes its not far enough out of parameter to throw a code its just a flat spot in the rpm band.

 

[Slightly Motivated]

Maybe you need new plugs/better spark plugs/have them regapped? I had this problem when i first pulley'd my car, and tr6 plugs fixed it right up. Only ever at WOT, almost like a sputtering. But i have no idea about the oil gauge :/

 

[SVTDice]

Is there any chance your fuel pumps may be maxing out? Or the fact that you could be pegging your MAF? I'd clean your MAF and check your plugs.

Whats your mods? Is it all stuck? More info please!

 

[SaleenCobraSwap]

Maybe you need new plugs/better spark plugs/have them regapped? I had this problem when i first pulley'd my car, and tr6 plugs fixed it right up. Only ever at WOT, almost like a sputtering. But i have no idea about the oil gauge :/

That sounds like what is happening, I will pull the plugs and check them today.

Is there any chance your fuel pumps may be maxing out? Or the fact that you could be pegging your MAF? I'd clean your MAF and check your plugs.

Whats your mods? Is it all stuck? More info please!

I actually don't know. I bought the car as it is last month, I usually do all my own builds but I'm completely new to modular motors, as well as superchargers so I'm quite out of my league.

Mods (according to previous owner):
Stage 5 Eaton
2.73 upper
Injectors
full exhaust

 

[SVTDice]

That sounds like what is happening, I will pull the plugs and check them today.



I actually don't know. I bought the car as it is last month, I usually do all my own builds but I'm completely new to modular motors, as well as superchargers so I'm quite out of my league.

Mods (according to previous owner):
Stage 5 Eaton
2.73 upper
Injectors
full exhaust

Yeah, You could easily be running out of fuel without a Boost a Pump. And could be Pegging your MAF, Honestly. I'd go to a tuner and make sure you are not leaning out. Otherwise you could possibly hurt the motor. Take it easy on her for the time being. I would still look at the plugs to be honest.

See if you can contact the owner and get a FULL Mod list, Also find out if the car has been Dyno tuned.

 

[SaleenCobraSwap]

Yeah, You could easily be running out of fuel without a Boost a Pump. And could be Pegging your MAF, Honestly. I'd go to a tuner and make sure you are not leaning out. Otherwise you could possibly hurt the motor. Take it easy on her for the time being. I would still look at the plugs to be honest.

See if you can contact the owner and get a FULL Mod list, Also find out if the car has been Dyno tuned.

I was told it was dyno'd by the owner, but I don't think I will be taking his word on much of what he said. Where would a boost a pump be located? In the fuel tank?

Just pulled the plugs and think it is time for replacement:

http://i1134.photobucket.com/albums/m618/durtbikedude365/sparkplugs/IMAG0423.jpg

http://i1134.photobucket.com/albums/m618/durtbikedude365/sparkplugs/IMAG0422.jpg

 

[SaleenCobraSwap]

Are NGK TR55 Iridium's ok to run in this motor? I asked for TR6's but they told me that was the incorrect plug. I know it isn't but the didn't have them in stock anyway.

 

[SVTDice]

Don't hold me to this but those plugs seem too hot for your Motor, Like too hot of a range. I hear they are for Cobra's in the Stock range. I'd take those out and put in either TR6's or Put in BR7EF's Its what I have. I have mine gap'ed at .32. Heres another quote from another thread. So as advice I would NOT use those plugs that they told you to use.

Stay out of the boost, that heat range plug will cause detonation at your mod level. They listed the TR5 for the cobra with stock boost and pig rich stock tune. They are right that it will work for that application.

Checking the plugs every oil change probably is not necessary. So long as they are torqued properly they will not get loose. You can't go wrong with the TR7ix plug. They idle great, hold their gap for a long time, and are all around low maintenance compared to the copper plugs.

"Plug gap is determined by boost level. You want to run the largest gap you can without preventing the electrical arc from jumping across the electrodes. If the boost is a little to high for a certain gap, then the compression in the cylinder will blow out the spark. We need your boost level to determine gap."

And as a final note. Go for a copper plug, TR6 or BR7EF Etc, Iridium's are nice. But I just don't find them worth the money. I can get all 8 Plugs for around 16 bucks or so at Advanced Auto.

Anyways, If you need anymore help. I'll be checking back or Inbox me. I just want to make sure everything goes okay.

 

[SaleenCobraSwap]

Don't hold me to this but those plugs seem too hot for your Motor, Like too hot of a range. I hear they are for Cobra's in the Stock range. I'd take those out and put in either TR6's or Put in BR7EF's Its what I have. I have mine gap'ed at .32. Heres another quote from another thread. So as advice I would NOT use those plugs that they told you to use.

Stay out of the boost, that heat range plug will cause detonation at your mod level. They listed the TR5 for the cobra with stock boost and pig rich stock tune. They are right that it will work for that application.

Checking the plugs every oil change probably is not necessary. So long as they are torqued properly they will not get loose. You can't go wrong with the TR7ix plug. They idle great, hold their gap for a long time, and are all around low maintenance compared to the copper plugs.

"Plug gap is determined by boost level. You want to run the largest gap you can without preventing the electrical arc from jumping across the electrodes. If the boost is a little to high for a certain gap, then the compression in the cylinder will blow out the spark. We need your boost level to determine gap."

And as a final note. Go for a copper plug, TR6 or BR7EF Etc, Iridium's are nice. But I just don't find them worth the money. I can get all 8 Plugs for around 16 bucks or so at Advanced Auto.

Anyways, If you need anymore help. I'll be checking back or Inbox me. I just want to make sure everything goes okay.

Ok thanks, I appreciate it. I didn't put those plugs in yet incase they were the wrong ones. Good thing too. Boost is at 14lbs, who makes BR7EF and the TR7IX? I also took my MAS out and sprayed it down with some CRC cleaner as well as a new drive belt incase the old one is slipping. Doubt it, but it seems to be due for a replacement anyway.

 

[CUINMYREARVIEW]

Got same issue

Iam having similar issue i keep getting P0148 code it was only happening ever once in awhile now its all the time i change fuel filter fprs checked for blown fuse's i changed my tune to just the street tune from street + and in stopd doing it in 3rd gear now only in 4th gear got any idea iam going to check my bap an make sure its wire before the fpdm and pull plugs and look at them and check maf to see if it dirty its got new battery new alt and its got the lfp over drive pulley i dont know where else to go

 

[SVTDice]

NGK makes the BR7EF and the TR6. I'd honestly go with BR7EF at .32. You can get them at Advanced, And a few other Auto part stores. But yeah, Glad you caught that. Another thing you may want to look into is your Fuel Rail Pressure sensor. They tend to go sometimes. But honestly I think it was more of a plug issue then anything.

CUINMYREARVIEW. I'd check your plugs and make sure the gap is correct for your power and boost levels. You should be fine with TR6's. They are good plugs. But in other case, I'd check and see if your MAF is pegging or your Fuel is running out. It could be a possibility in the colder weather. Colder weather = Dense air, Dense air = More power, = More fuel and Air, And so on. So, If you are only getting this issue this coming winter. Then that is more then likely it. I'd call your tuner. To be honest.

 

[Kubin-B]

Yeah sounds like you are blowing the plugs out. TR6 gapped between .30/.32 would be the first thing i would do.

 

[SaleenCobraSwap]

I checked the gaps on my old ones today, they are gapped at about .34-.35 on all eight.

 

[01yellercobra]

I checked the gaps on my old ones today, they are gapped at about .34-.35 on all eight.

You could try cleaning them up and closing the gap. But they are cheap enough that it might be worth getting some new ones and gapping them at .030". I ran that gap at 14psi and never had an issue with spark blow out.

 

[SVTDice]

I would still use BR7EF's or TR6's before you put those old plugs back in. I'd play it safe man.

 

[Rossim22]

Definitely go another heat range colder. I'm at about 17lbs with the 2.76/4lb posi port and am running 8's.