How could spark plugs decrease overboost from a bad WG diaphragm?
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How could spark plugs decrease overboost from a bad WG diaphragm?
I popped a hose off my wastegate that ended up ruining my WG diaphragm. Which resulted in overboost problems, sometimes as high as 1.8
Yesterday some new spark plugs arrived. They're the Bosch w7dtc tri-electrode spark plugs that are recomended for my 86KTQ. I decided to through them in and go for a test drive. Acceleration was a lot smoother. The odd part is that with these new plugs I cant get it to overboost 1.5, it was overboosting to 1.5 or higher and cutting out. Now it seem to get right up to 1.5 and I can hold it there for a few seconds before it cuts out. Also, before the spark plugs when it cut out the car would jerk hard. Now its very light. I know for what ever reason my car is running lean. Any takers as to whats going on? Im going to recheck the injectors but besides that is there any way to adjust the mixture without special diagnostic tools?
Yesterday some new spark plugs arrived. They're the Bosch w7dtc tri-electrode spark plugs that are recomended for my 86KTQ. I decided to through them in and go for a test drive. Acceleration was a lot smoother. The odd part is that with these new plugs I cant get it to overboost 1.5, it was overboosting to 1.5 or higher and cutting out. Now it seem to get right up to 1.5 and I can hold it there for a few seconds before it cuts out. Also, before the spark plugs when it cut out the car would jerk hard. Now its very light. I know for what ever reason my car is running lean. Any takers as to whats going on? Im going to recheck the injectors but besides that is there any way to adjust the mixture without special diagnostic tools?
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Re: are you sure you trashed the WG 'fragem?
I never had any overboost issues before I popped the hose off the WG. I'll take a look around to make sure there isn't anything else loose. I just think its odd that the overboost changed when the only thing I did was put better spark plugs in.
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Re: are you sure you trashed the WG 'fragem?
The line I blew off was the line at the top of the waste gate, Looks like a small vacuum line. Everything looks to be in place.
Something else I find odd is that my engine has been making sounds almost like a bypass valve when I shift during hard acceleration. I dont have a BP installed yet. Any idea where that might be coming from?
Something else I find odd is that my engine has been making sounds almost like a bypass valve when I shift during hard acceleration. I dont have a BP installed yet. Any idea where that might be coming from?
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ehh... like an air rushing sound?
"Something else I find odd is that my engine has been making sounds almost like a bypass valve when I shift during hard acceleration"...
like the sound your car would be making if it were to, say, have a hole in a hose, a loose connection, or other boost/vac leak?
I'd check there.
like the sound your car would be making if it were to, say, have a hole in a hose, a loose connection, or other boost/vac leak?
I'd check there.
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Re: ehh... like an air rushing sound?
I've gone through all the rubber hoses and they look good. Since I hit 1.9 a couple times when it was overboosting, I'm betting I blew the IC. Just seeing what others thought.
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Re: ehh... like an air rushing sound?
The MM hose is a good suspect for that as well. Take it off the car to inspect it properly. They usually pop on the underside due to the geometry. Wipe it down and poke at it.
BTW: 1.9 means you were potentially MUCH higher. 1.9 is the max your dash will display. Past that it will not resolve.
BTW: 1.9 means you were potentially MUCH higher. 1.9 is the max your dash will display. Past that it will not resolve.
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