it all started with a pulley upgrade 2.76 then things started going bad,fuel pressure was all over the place,when it went to 70 psi with hand held gauge car ran awesome so we thought fuel pumps were bad so we replaced them with focus pumps and pprv delete car still runs terrible under boost ,we did have a driver module go bad also and replaced b4 pumps have noticed boost pressure goes up extremely fastit did pull a code for map sensor cant remember # but it wont repeat pullin a code car does have a boost a pump for a while and has new fuel filter has older lidio tune but changed to stock tune also and still messes up any help would b so greatly app thanks
03 cobra out of options please help!!!!
- Thread starter 9secondnotch
- Start date
oil was changed 2 or 3 weeks ago and we swapped out the frps with mine off my 99 cobra and didnt help and steve from tousley said they were the same and interchangable
So you're running a stock tune with a 2.76 upper? If so there's your problem bud lol
i just flipped the switch to c if it would make a diff but with barely makin boost and it still ran terrible,could the stock mass air b bad or maybe the map sensor can they take 15 pounds?
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and when it was flipped back on stock tune it had 2.93 pulley on it and it still ran like garbage car is actually mine, notch is my brother tryin to help figure it out for me, and btw like he said any help is much appreciated!
I can't get the scanner to show that I did turn down the bap though to a 1/4
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Does it break up only at WOT? Buck, shake, hesitate?
No it seems to do it on the way to wot seems like it does better the slower u get into rather than just jamming the gas
This happened only after changing the pumps? You've replaced just about everything else.
Drop the tank and see what the pumps look like. The lines arent kinked or poped off the fuel pumps.
Also, go get it professional tuned or get a Jon Lund email tune. Plus DL the software to datalog. Its free from SCTs website.
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Ok no it was doing it before the new pumps were put n thought it was week pumps bad pressure valve n tank but it still act up
Could I somehow use my s t tuned to check his car or is it a program to use w a laptop thanks
What prove did you have that the pumps were going bad other then high fuel pressure? Also I blew my FRPS at 78psi. I know you said 70 psi somewhere but if it was replaced then that should be fine.
You have to have an SCT tuner and a laptop. I wish you guys were closer to me and I would see what I could find for you guys. But from Michigan to Wisconsin isnt exactly a quick trip.
But go ahead and get a good tune on it and see if its tune related. After that I would drop the tank and see how everything looks. Lines have been known to pop off, fuel pumps have been plugged in the wrong way,etc.
Get the tune and drop the tank and you should have your issues nailed down or atleast have a better idea as to what is going on.
Ok just dis tank today so I think that is ok so I guess I will see about the sct stuff so I can log it and look at things thanks then tune
Also, Can you post the cars FULL mod list? Leave nothing out. And everything that you have replaced.
Ok I will get with my brother n mornin and write everything out thanks for the help!
yea you need to tune that thing, it sounds like your either running no tune at all for the 2.76 upper or you have the shittiest tune known to man
Let me start off by saying i bought this car 4 years ago, it had 30,000 on it had already been tuned by lidios and made 465. First couple of years only did routine maintenance,well this year put a jlt cai, acuufab single blade tb as well as plenum. All was good and car ran better and felt very strong...until i put a 2.76 sc pulley and then things have went bad, noticed fuel pressure all over the place so we changed frps and driver. Nothing seemed to fix but was better,so put 2.93 pulley back on and problem still there and soon as it gets into boost it just almost seems like it starts to miss and have to get out of gas very quick. Also did put focus pumps in yesterday..still there.. I wouldnt think it would b in tune since it was so abrupt...but i am definately not the brightest guy.. Thanks for all input!
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