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HELP--Stranded after changing fuel filter and injector cleaner...need help FAST

1234 Views 7 Replies 8 Participants Last post by  speednick
I'm stuck and need help. 78 280z manual. I changed fuel filters yesterday and also put a fuel additive called SEAFOAM in the gas, oil, and vacuum lines. I've used this product a lot for my vehicles for the past 8 years and have never had problems.

After changing fuel filters i started the car (idle) and everything looked ok. I then put the cleaner in the gas tank, crank case, and the brake boost line on the firewall (with engine running) and let the car sit for 5 minutes (engine stopped). One thing that I noticed different was when I took off the main brake boost line the engine actually ran much faster instead of the RPMs dropping like usual even before i started pouring the SEAFOAM.

After letting it sit I then went out for a drive to clean the system out of all the additive in the vacuum sytem. Idles great now, but when I give it much of any gas it bogs down. I let off and then rpms start to come back but then is also starts to smoke black as it still runs really rough. If I cruise at 2000 rpms and hardly any throttle applied it runs really smooth, but any power needed it then starts running rough.


One more thing, I checked the CSV earlier in the day and that isn't leaking. I reinstalled the valve.
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You did change the oil right? You should not leave seafoam in very long in the oil, change after a light drive around the block. Some cleaner can make the car run like crap til its out of the system so diver gingerly til its out.
this sounds like a vacuum problem. Does your vehicle have an EGR valve? Also check crankcase ventilation.
I notice some people using seafoam complain that it badly fouls their plugs as a side effect of loosening all that grime, you might check that. Also some people have had trouble with their O2 sensor after using seafoam. Easy to check both of these, and double check that you haven't caused a leak in the vacuum lines.
"...brake boost line on the firewall (with engine running)..."

Why not use the vacuum line running to the FPR? Could the brake boost line be a prob?
did you look at the spark plugs? maybe they have gunk in them and won't fire properly
Or the gunk came out from behind the rings and now compression is down...
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