Have a fuel pressure gauge? What does it see when the key is set to ACC? What does it see if you start your truck and pull the vacuum line on your regulator, or have you swapped out for an aftermarket?
Two dead cylinders... I need help....
- Thread starter SWThomas
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I would also try swapping those two injectors with two on the opposite bank and see if the problem swaps banks as well.
Stan my truck has the same issue... it was shaking, then a CEL went on, and i pulled the plugs and found that all the drivers side plugs were black with Soot... ?
cant figure out the code... gotta get a code reader... but im guessing its a valve train problem...
I'd say high/low relay on the pumps issue, if not that check the dropping resistor. It very well could be the cp's bro. I just had a similar problem last month, kept me from running at Lfest. They all ohm'd out like they should've, but under load they'd just give up. Same conditions with the plugs. Took 8 new Accels (which I would recommend those over the GMS anyday: cheaper and you don't hear anyone having problems with them) to get the dead cylinder/s to pick back up.
You can check to see if the computer is sending a crappy signal with a "noid" light. It should flash with each pulse...
On my buddies cobra, it was the computer that went bad. The one guy said to us that there was one Injector driver IC for each two cyl. Thats why when it went bad, he had two stuck open injectors. We could smell gass pretty bad when standing behind the car.
On my buddies cobra, it was the computer that went bad. The one guy said to us that there was one Injector driver IC for each two cyl. Thats why when it went bad, he had two stuck open injectors. We could smell gass pretty bad when standing behind the car.
Usually when it is a whole bank that has an issue it is a cam timing issue.
ecoastkid is right to. In our Ford software we have the noid lights, the same light supplied works on both the injector and the coil. Plug them in, crank, and they should flash when the coil/injector should fire.
First thing for you Spencer is try swapping those injectors with others. Check and see by pulling those same plugs and see if it makes a difference now. If it doesnt make a difference you just canceled out those injectors themselves as the issue, but not necessarily the ECM or injector information. If the injectors are not being told to close, spray, open, etc. then the injectors are probalby fine it might be in the ECM or the tune.
Tunes do have faults too, and can go bad at times, if a virus infected your computer it could have affected your tune on your laptop as well. I think that is the most common way of the tunes going bad... Stan
Yup! thats what i thought... i have no valve train noise (indicating bent, broken, or crapped out valve) but all the plugs are soot colored on the drivers side, and the truck runs like crap...
SO the motor comes out and gets new heads (big ported heads)... and if the current heads on it are good then ill just sell em..
just was making sure im going in the right direction stan...
Your chain could have jumped a link, it happens I've seen it before. Not only that, but very very seldom, if the proper torque spec or loctite fluid wasnt used then the cam bolt can come loose and the cam will will lose it degree at the least. Bob knows what I'm talking about (insert smiley hiding under chair) ... Stan
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I just checked compression on both cylinders. They both read 150 PSI. I can now rule that out. I spoke with my tuner and he's kind of baffled also. I'm not able to datalog anything yet because I'm still trying to get Live Link to work with my Windows Vista laptop. I'm thinking it's either computer related or maybe there's a short in the harness somewhere. It may be computer related if there's any truth to what ecoastkid was told...
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Yeah, but if the cam bolt came loose I would hear some kind of rattling like Bob did. I hear no rattling.
I no longer have a resistor so that theory is out. I swapped all 3 of the fuel pump relays with the spare I have in my glove box and it made no difference.
oops sorry Spencer that was for Jay/BDA1855 lol...
OR if you have filed down your cam gears to get them to degree properly... and the gear slips, you could be off 5-6 degrees.. which is where i may be...
FTL!
The fuel pressure is fine. It's where it always is.
Sounds like it is in your ECM or tune posibly...
Do you have an old tune saved you can load, or your stocker and see what happens...
Do you have an old tune saved you can load, or your stocker and see what happens...
I drove to the track on pump gas. Drained it all out and filled with race gas. Drained it all out at the end of the day and refilled with pump gas. I filled the truck up yesterday at the same station I always fill at. I seriously doubt it's the pump gas I'm using.
The tunes on the XCal2 have been there since my tuner tuned the truck. I haven't made any changes or uploaded any updated tunes to the XCal2. I'm thinking ECM. But I'll swap the injectors around tomorrow and see what happens.
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Yes, but see what I'm saying is that will only happen if that cam bolt came loose or wasnt properly torqued or loctite wasnt used. We even have stock Ford cam bolts in Dantes race truck, there is no need for aftermarket botls or anything special, hell look the 4v cams don't even have keyways and they are held on by almost the exact same Ford bolt. They cams shouldn't slip in the gears... Stan
Hrm.... I suppose it could be the ECU, but I'd probably lean more twards a harness issue there. One would think that if it was an ECU problem the issue would be across the board, not isolated to two cylinders.
Course, we ARE talking about Ford here, lol. Hope ya get it figured out Spence. At least you know it's nothing internal.
Course, we ARE talking about Ford here, lol. Hope ya get it figured out Spence. At least you know it's nothing internal.
yeah... i used locktite, and i think the bolt was tq to 100 ftlbs... cant remember...
if it aint the cam slipping then i may have a busted tensioner chain or something like that...
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