I have a 97 honda civic ex coupe d16y8 that was turbo charged for about 2-3 months and now is back to nat. aspiration. I found that ever since the turbo was on and now that it is off, there is consistantly a studdering problem that is becoming more and more persistant. (When driving it wll feel like a fuel cut, and studder then go back to ok. It takes about 5-10 mins of driving to become noticable. It seems to happen worse or more after high rev.(rpms). When the problem starts to occure, my boost/vac. gauge will drop from a normal 20psi to close to 10psi. the engine begines to sound as if it may stall the recovers momintarily. Could this be timing? I have replaced my fuel pump, my spark plugs, and checked my injectors. (All is good there.) All my vac. seals are ok. There is only bout 60,000 miles on my car so timing belt seems slim chance. Any ideas? This problem is really frustrating. If anyone knows what this could be, or can help in anyway, please let me know. thanks.

NOW...its been about a year, or 10,000 miles since the problem stopped, and its back. I changed the distributer rotar back then and it seemed to fix(until now). Now its back. I have new rotar, cap, new spark plugs and wires, checked the PCV, tis ok. my TPS seems ok too. I can't test my IACV...I took it to the dealer and it would not act up for them!? No idea what to do know, any insite? maybe timing, valve adjust, head gasket(how would i check these if you think they could be?)PLEASE HELP, thanks.

 

I put this one up again...they keep wackin my posts for some reason.

 

k guys, i now know its not fuel related (fuel press. gauge)!? its electrical or vacuume...

 

im thinking head gasket.

 

was there a boost dependent FMU? Maybe its still there?

 

I thought that too at first, FMU is no longer, for some time now, bout 10,000 mi.