taisback

Hi All Name is Mike I have a 89 with 72,000 miles on it and ran into a big issue . one day car would not start so found out had low fuel pressure and put new relay and module in and decieded to go ahead did fuel pressure regulator too . Car starts check pressure 44psi happy but car has a crappy idle and at 2000-3200rpm engine acts like it runs on 4cly so replaced ignition module , wires , cap , rotor , plugs and ran compression test less than 6 psi per cly differance , ran car still runs same . pin test check codes none , change ECM (NEW NOT REMAN) , changed coolant temp sensor and ran car again and still run the same . Any ideas Poss injectors , mass air flow , ????? Any help before my bank account goes negative

larry00

First off our reformulated gas and even worse gas with Ethanol at best last 3 months and I have bought bad gas away from home that will cause the symptoms you describe a short time after putting it in..
Use fuel conditioner any time your vehicle sets up for extended periods.
Put in gas treatment burn out most of the fuel and put in some fresh.

I buy Premo at the Shell Station by the University where the Professors gas their Volvos and Beamers !
Premo sits too long in Mom and Pop Stations and the F ing Ethanol attracts water like a magnet !


Next :

Try noid light on injectors ! Noid Lights are not pricey if you shop around.
I'm sure you have done the obvious . Air Filter , fuel filter ! You can make or buy [ NAPA maybe ] a harness to check your TPS [ Throttle Position Sensor ] , Takes a special socket to remove oxy sensors soak over night in gas and clean ! They hardly ever need replaced .

At night start engine open hood and look for wires grounding out !
Throw a can of injector cleaner in occasionally !

I'm sure someone will have other ideas and this is the best place for advice and Ideas !

Been a while since I messed with a L 98 but they are good dependable engines.
Still could be Distributor , PV valve , Knock sensor and about a hundred other things. Also did it hold the 44 lb's without leaking down ? Eng off and running both ways ? Off shows if an injector is stuck open.

Hopefully you have a FSM [ factory service manual ] ! They often go for cheap on E Bay !
Learning to maintain and do light maintenance on your car is good all the way around .

WW7

If its a 89 it could very well be the injectors if they are the original Multecs that came stock. To check this out you will have test the injectors with an Ohm meter to see how much resistence you have going through the coil..Below is the link to a video to show you how to do this..If it turns out to be bad injectors the guy on the video is the one to see about getting new injectors..WW

You want to watch the 5th video down on testing fuel injectors, watching 3 and 4 wouldn't hurt either...

http://forums.corvetteforum.com/c4-t...questions.html