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Gan 2 brat - Surging/bucking problem


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Problem usually occurs while under load (going up hill) or accelerating up to speed (45-60mph).

 

Problem is... giving anything more than light throttle (like... an 1/8th) brat will start bucking, seems like its running out of gas or something like that. The problem is intermittent though. There are times where you can go full throttle, or anything in between and it runs just fine.

 

Problem has occurred on the old Hitachi, and now on the weber. I also changed manifolds, to one that was de-emissioned.

 

Fuel pump is new, replaced by previous owner, is hardwired to fuse panel, and the relay thing was broken (i guess..)

 

New fuel filter in engine compartment. NO fuel filter before pump... i bought one to put in though.

 

My theories so far:

Stuff in gas tank, clogging pump intermittently.

Water in gas tank (i bought some fuel dryer to throw in, but haven't done it yet)

Catalytic converter is borked, cause weird issues?

 

Any thoughts?

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My turbo did that for a while. Switching from 87 octane to 93 almost made it go away, then it only happened at WOT.

Timing was advanced too far (eyeballed it without gun). Set timing correctly, now it's all fixed. Hasn't happened again on two tanks of 93 or half a tank of 87.

I hope it's that easy for you.

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Well, I put a fuel filter in before the fuel pump this morning. And I added about a 1/4 of a bottle of gas drier to the 3 or so gallons of gas that were in there.

 

No problems afterwards on my way to work, or on my way home. Nor on the trip to my parents house, then to dinner, then back.

 

So... hopefully just bad gas, and after talking with some other local people, the likelyhood of this station having bad gas occasionally is pretty good. Really only happens with their premium though, which is what my roomates put in it when they borrowed it a while back, and since then it has had this problem.

 

Sadly, I have nearly 3/4 of a tank of premium gas, from the same station, sitting in the RX. Could water in the gas cause massive detonation to blow 3 of 4 cylinders, and take the rings in 2 of those with them?

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Sadly, I have nearly 3/4 of a tank of premium gas, from the same station, sitting in the RX. Could water in the gas cause massive detonation to blow 3 of 4 cylinders, and take the rings in 2 of those with them?

I think you should get a lawyer to look into that for you ;)

 

Say the gas caused the crack in the windshield while you're at it!

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Problem usually occurs while under load (going up hill) or accelerating up to speed (45-60mph).

 

Problem is... giving anything more than light throttle (like... an 1/8th) brat will start bucking, seems like its running out of gas or something like that. The problem is intermittent though. There are times where you can go full throttle, or anything in between and it runs just fine.

 

Problem has occurred on the old Hitachi, and now on the weber. I also changed manifolds, to one that was de-emissioned.

 

Fuel pump is new, replaced by previous owner, is hardwired to fuse panel, and the relay thing was broken (i guess..)

 

New fuel filter in engine compartment. NO fuel filter before pump... i bought one to put in though.

 

My theories so far:

Stuff in gas tank, clogging pump intermittently.

Water in gas tank (i bought some fuel dryer to throw in, but haven't done it yet)

Catalytic converter is borked, cause weird issues?

 

Any thoughts?

Are you useing 93 grade fuel or better all early subis use hi test

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