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General breaking up at 5500rpm

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Mike9490

Proven Member
43
8
Apr 23, 2017
Livonia, Michigan
So all of a sudden my car starts breaking up at about 5500rpm. but the weird thing is its not every time. I drove it yesterday first pull broke up second one went to 7500 no problem 3rd time broke up 4th time fine and 5th time broke up. when the car did it the first time about 2 weeks ago I replaced plugs(BR8EIX) gapped to .018. when I replaced them the car ran just fine for my half hour drive home except the last 2 pulls I tried to do broke up again. I just found the specs for the ignition coil so I will be testing that when I get home again to verify its good. ordered a new set of wires for it will get those tomorrow night. but the only thing I did different was I got gas at a different station then usual. the next time I drove it after fill up was when the issue started. so I put stabilizer in the fuel to try and correct it. but not all the way. so new plugs, check, new wires(tomorrow), going to verify the ignition coil tonight against one I have that's my spare. also going to do a compression test just to be on the safe side and boost leak test also if I have the time if not this weekend I will do it. car sat all winter after running perfect last year. and had no boost leaks so doubt there actually is but just want to verify nothing funky happened.

has anyone else ever had this issue? and what was your solution?
I've also been down on boost from what it was tuned for. currently running 28 and was set to 35. but nothing has changed and that was done about 2 years ago.

Thanks in advance. hopefully its something dumb like the gas is actually bad or the coil is bad. but just wondering if anyone's experienced this intermittent weird breaking up before.
 
Well when I got home I tested the coil it was good. Found a loose wire on the ignition control module and fixed that took it for a drive runs fine now. Hopefully that was it
 
Those things are hard to chase down sometimes, glad you found it and have the gratification of knowing "I fixed it" like we all have to do on these! :)
 
Well I thought it was LOL. It pulled fine 3 times for me then me and the gf went for a cruise for like 30 mins and the last time I got on it it broke up around 6500 or so. Unfortunatly I didnt have my computer hooked up. Go figure! I'm leaning towards the gas now because I put stabilizer in it and it helped a little so I'm gonna cruise around and burn this gas out and get known good fresh gas this weekend and go from there. I only put a bandaid on it to verify the icm was the issue but tomorow I will solder there connection and fix it properly. Will update as I drive the car though
 
What are you running for a boost controller? I have a gready profec b spec 2 and have break up issues occasionally depending on weather. Its normally when im not making enough boost that it breaks up.
 
I had this issue one time. Pretty much the exact same scenario, breaking up at 5500 to 6500, randomly.
I had supertech dual valve springs and i found that one of the inner springs on the intake side had broken and was free-spinning. If you have dual springs, and exhausted all other solutions, I'd recommend taking the valve cover off and taking a gander at your springs.
 
E-85 got gas a week ago from a different station then usual. Dumb I know and I think it was bad because it all started the next time I drove it

@ boosted thanks! Never thought about that might have to peel the cover off and check that out. How did you find that one? And I'm not sure if they are dual springs I dont think they are though
 
Some stations might still have a lower ethenol content from winter blends. I just got summer blend within the last 2 weeks. The staion closest to me in Wisconsin took a while to empty their tanks of winter mix. If you're on winter mix thats more gasoline less ethenol and you will run rich and could have rich knock. I would definitely try to run the fuel out and go back to your trusted station at least for a while. Might get lucky enough. .. Should also log for knock or make shure your check engine light is set for knock in link
 
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Well I Havnt had a computer on when its been messing up but during one good pull I had .4deg of knock today unsure of how much there is when it messes up. But just sure hoping its bad gas. Do you test your ethanol every time?
 
I know right away from my air fuel guage when the ethenol content is down. And with my horse power I run a very safe tune on the street.So I never see any knock even if I get low ethenol fuel. If im pushing 40 psi and aggressive timeing it does get picky on ethenol content tho.

Do you have a afr gauge?

The low boost situation would be my primary focus. It can cause rich knock and breaking up. I would definitely recommend a boost leak test. And check the waste gate with compressed air and a regulator before I threw money at anything.
 
the low boost was me. I turned it down on the controller about 2 years ago when I was having fmic problems. I do have an afr gauge and everything looks fine on that while driving and while idling. while idling it bounces back and fourth between 14.2 and like 15.6(yes its set up for E-85) just reads normal readings is all.
 
so quick update on the car. about a week ago drained all the gas out, didn't find anything bad in there though, but also didn't test the gas as I don't have a tester. I pulled the injectors while I was waiting on my buddy to come over and help me drain the gas and cleaned those out, 2 were pretty dirty and sticky. put them back in with some fresh gas in the car and went and filled it up. pulled once fine and then broke up again a few times. well I threw some seafoam in the tank and drove to Milan last weekend to help clear out anything left in the injectors. driving home from Milan car was awesome! pulled super hard and revved all the way. drove it to work today and took some guys for a quick spin, seems to be all good now car runs like a raped ape now! just waiting on my new axles to come in the mail and put on my new tires!
 
That's what my verdict is LOL. may have been the gas but im starting to doubt that more after seeing the injectors!! that seafoam really does work though man! I was always skeptical about putting it in cars. but seems to have done the trick I needed!
 
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