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Discussion Starter #1
Hi everyone...i am new here
I have a 2001 Mustang cobra with a v2 vortech. The car only has 34k:)

I have a question about fuel problem with my car
So i went into a shop that is known to work on mustangs. They did one pull to see wat kind of number i would get with the vortech. They realized that my car was running lean and not tune right, so we made an appointment for next week to get it tune. I dont know a lot about cars but i know enough to get by. ITs a long story but bottom line they told me my car is fine and that it made 400rwhp with only 5 psi. a day later i can tell my car was acting slugish, rpms where jumping around and made a clatter type noise when at 2100 to 3000. Is this Pistons Slap? Bottom line is should a shop have even tune my car when they knew my car was running lean and may need a new fuel pump?? I think my motor my be pinging.
 

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That's not piston slap, that's detonation, which will kill it fairly quickly on boost.

If they had it on the dyno, they should have given you a printout that shows exactly what you're making, and what the air/fuel is on it.

400 sounds a bit high on 5lbs for your car, probably 360-370 at the rear wheels with 5lbs and no intercooler.
 

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It sounds like they have too much timing in it for you not having an intercooler, and the hot summer days being here to me.
 

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Several things have to be checked,

1. Detonation (caused by timing, fuel ratio, heat)
Things to do:
a) Visual inspection of the spark plugs
b) Get the car on a dyno to measure Air fuel ratio along the RPMs. Supercharged cars need to run on the rich side
c) measure intake and discharge temperatures
d) verify MAF voltage
e) use the right spark plugs (heat range)
f) check COILs
g) check exhaust gas temps (this with air fuel ratio will tell a lot to the tuner)..also done on the dyno.
h) Fuel pressure drops

These are the basics.

Any dyno run will result in a printed sheet containing the data.

BTW...fuel ratio is the parts of AIR vs FUEL expressed in a ratio such as 13:1 (13 parts of air/ 1 part fuel)
Read this Air-fuel ratio - Wikipedia, the free encyclopedia
 

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i feel its the shops fault for not doing things right. What is your input?
I feel they did what they could. They checked your car, TOLD you it's running lean, and set up an appointment to make it right. In the meantime, the impression I get from your story is that you're out beating on your car despite knowing it's lean and doing a nice job of causing some detonation, and now you're looking to point fingers. The shop you visited has no legal liability that I can see nor any reason to lose sleep if and when you scatter your motor all over the interstate. I sure wouldn't.
 

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Where do you see that he said the he knew it was lean after the tune? From what I can decipher, he said the shop said it's fine and made 400rhwp and that it was lean before the tune.

Either way, I damn sure wouldn't be out beating on it until I got it fixed. Hypercraptastic pistons + boost + detonation = ring lands missing.
 

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I see that they made one pull, saw it was lean, and made an appointment to actually tune the car next week. I am assuming that appointment hasn't happened yet.. if it has, I would agree with you Rich. However, blabbing on the internet won't fix anything, the OP should be contacting the shop and scheduling time to make it right.
 

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I see what you're saying now, when you read this story, it leaves too many holes for the reader to assume what they want.
 

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Discussion Starter #10
My bad that i didnt get the whole story...the story is way too long. Ive been dealing with my car in and out for the past month.
"you're out beating on your car " UM ya i dont know where you got that with my story. As you can tell i dont drive the car much. 2001 with only 34k. I do not beat on my car. Yes i have already got my car tune by the shop. Ive been going to the shop for years and never had any problem. The manager there which has no experience with tunes did my car the first time to see where my car was at. Dont ask me why....i have no idea why they let him do it. He went full throttle with my car not even lookin at my fuel which found out afterward when the guy who does the tuning notice it was runnin lean. I talked to the tuner for about an hour talking about. We talked how i have a bad fuel pump blah blah. He said no problem, bring it in next week and i will tune it and everything would be good. Before i go one...my car was running very strong, no sounds, no hesitating from the engine, rpms where fine, speedometer working, and not being sluggish at all. I droped off my car with him knowing it had a fuel problem. I dont know everything about car but i know enough to get by. I get a call from the shop saying everything is great and it made 393 rwhp...Long story short the next day my car was slugish, hesitating from the engine, rmps jumping etc.....pretty much tune was all wack after he told me everything was fine..So i didnt really drive it at all then i not to mention it i didnt step on it at all and i was told by one of thier employees to keep it under 2500 so i did. a couple day s pass and my engine started to make noise. they did a diagnosed and they said it wasnt knocking and they couldnt retune my car that day and said to come back. i asked how can you tune a car to begin with a bad pump?? they really didnt answer. ANd for some reason the tuner didnt even mark my fuel for the car. Ill have to finish this later.at work
 

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The extra info would have been nice to have to start with. The bottom line stays the same though, work it out with the shop, blabbing about it on the internet is going to fix nothing, to include your car. It could be as simple as you having an intermittent problem that doesn't show up on the dyno.
 

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Discussion Starter #12
shop going to fix issue

The extra info would have been nice to have to start with. The bottom line stays the same though, work it out with the shop, blabbing about it on the internet is going to fix nothing, to include your car. It could be as simple as you having an intermittent problem that doesn't show up on the dyno.

I wasnt really blabbing about it i just wanted to see what other peoples opinion would be. Look s like the shop is going to fix my problem.:bigthumbsup...well hopefully
 
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