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Car sputters when trying to boost

Beelzeboul

Beelzeboul

New member
I recently checked my LTFT and FFDP had said based on reading I had a vacuum leak I had a very bad leak after reinstalling a rebuilt supercharger at the TB that shot coolant out my intake and later burned white smoke for about 3 minutes. everything was fine but after installing headers I realized the idle was rough and WOT was even rougher I definitely can identify the sound of the leak after hearing one now and know it is coming from around my driverside. Even though I just replaced this gasket I think the spit of coolant it ate before being remounted took it's tool this is based soley on the vacuum leak LTFTs coupled with an intermitent coolant light even though my reservoir is full suggesting air bubbles in the system.<br>
<br>
Planning on chasing the leak with some starting fluid and making sure its coming from where I believe and than replacing gasket<br>
<br>
if anybody know any other likely culprits I could plan on checking if it isn't my TB gasket would be appreciated<br>
<br>
Thanx
 
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Re: Vaccum leak cpled with Intermitent coolant light

Yeah sometimes you can almost hear the leaks and almost pinpoint them. Just do what u said and spray around the tb area and check your vacuum lines.
 
Re: Vaccum leak cpled with Intermitent coolant light

Spray...FYI Looking at the res is only a measure of how much is in the res....has almost zippo overall to do with what's in the radiator. Always check radiator when cool.
 
Re: Vaccum leak cpled with Intermitent coolant light

yeah should have specified when I was checking coolant I would check and fill the radiator

took the starting fluid to it today its coming from right under my TB so its either my egr blockoff off or a bad tb gasket going to pick up a new one and inspect the old one

mentioned reservoir bill cause on my ole dsm the sensor for coolant was in the reservoir (not as stupid as I appear) :)

thanx guys
 
Re: Vaccum leak cpled with Intermitent coolant light

Bill you and dsm are by far the most patient people on the site when it comes to helping people . alot of the more experienced people on these forums grow more and more frustrated with nubs and nub questions and omg my car won't start issues. So I thank ya bill and the next time you say sump-tin that offends me I'll go wipe the sand out my vagina and probably take you advice just like I did with the headers :)
Thanx
Robb
 


Re: Vaccum leak cpled with Intermitent coolant light

so my LTFT's seem to be back in order peaking at about 7 after letting off the throttle and dropping to -2/4 as I open up

still only reading -10psi boost at idle

also when I went WOT I had the engine throw me a code for a misfire in cylinder 3 just replaced all my plugs to one heat range cooler for the pulley
probably shouldnt be messing with WOT till its tuned for them was my assumption but I'm thinking ill replace the wires anyway unless that would be extreme

in either case would the low psi at idle suggest a blown SC or LIM or UIM.

in my search for leak I went around all of the sc gasket and no increase in idle produced
 
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Re: Vaccum leak cpled with Intermitent coolant light

That low psi would be perfectly fine since you said psi and not hg.

Take a look at the differences between hg and PSI. Two different scales for the same basic measurement.
 
Re: Vaccum leak cpled with Intermitent coolant light

I was thinking that ffdp had told me something to those regards . so I'm having a problem now where I am getting a misfire in cylinder 3 anytime I get over about 3.5-4k rpms which is right around the same time my boost would be kicking on I was told cylinders 3 and 5 tend to run the leanest and would be prone to this

is this something I should be able to drive with and take it easy on the ole girl until I get a tune?

is it something that could result in an ending involving a BOOM
 
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Re: Vaccum leak cpled with Intermitent coolant light

Coil, wire or plug are the most common.

Which coils are you running, stock or MSD?
 


Re: Vaccum leak cpled with Intermitent coolant light

sorry bill didn't even see this response this morning when I was looking through must have forgot to refresh. stock coils and wires plugs are NGK tr6's

checked the plug today fearing the worst and half expecting a bent tip to find it was properly gauged and the plug was all good






the first video you can hear what has been happening to me as far as almost a stutter when the supercharger kicks in

the second video shows how even when opening throttle so long as I dont hit boost it cycles fine
 
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Re: Vaccum leak cpled with Intermitent coolant light

aight ill swap the plugs wires and injectors to different cylinders and see which one it changes too and hopefully get an answer thanx bill
 
Re: Vaccum leak cpled with Intermitent coolant light

so I swapped my wires was still getting the misfire via same plug and different wire so I swapped plug with cylinder 5 and i'm not getting the ses code anymore... Still get some bogging when opening throttle up but it sounds alot cleaner. after examining spark plugs none had any black on them suggesting a rich ratio and both were in good condition

I think on my next trip to the JY imma have to pocket an injector as thats the only thing I could imagine having damaged while doing my SC swap and would produce an erratic misfire like im getting . if on my next run I end up getting the same code

Would that suggest my injector is bad?

is there anything else I should check before grabbing an injector?
 


Re: Vaccum leak cpled with Intermitent coolant light

so after swapping plugs and than injectors I'm no longer getting any misfire codes still kinda feeling like it at high rpms but its difficult to tell between a misfire and backfire with unrestricted exhaust

while swapping injectors I noticed my rear middle injector had what seemed like a disconnected harness possibly from header installation while moving wires to disconnect fuel rail.

Could a lack of fire in that cylinder cause the front cylinder 3 to misfire or shoot me a misfire code for it?

now that my problem has apparently fixed itself should I be concerned.....
 
Re: Vaccum leak cpled with Intermitent coolant light

And ...say you've unplugged the car and rolled the motor over a few times w/o doing a case learn. I could see that confusing the pcm on which cylinder. Possibly.

I've had two out of all the swaps I've done, when fired up they ran horribly. Checked everything and still ran horrible. Did a case learn.... amazing, perfect running, ...
 
Re: Vaccum leak cpled with Intermitent coolant light

Beelzeboul said:
Bill you and dsm are by far the most patient people on the site when it comes to helping people . alot of the more experienced people on these forums grow more and more frustrated with nubs and nub questions and omg my car won't start issues. So I thank ya bill and the next time you say sump-tin that offends me I'll go wipe the sand out my vagina and probably take you advice just like I did with the headers :)
Thanx
Robb
Click to expand...
Are you talking about me? I'm touched :D
 
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