Randomly runs rough

[dansformula]

Hi i have a 94 lt1 which runs fine most of the time but when you get on it then let off and cruise it'll start chugging and missfiring but will go away after like 5-10 seconds. Any tips would be appreciated thanks

[dansformula]

Any Ideas? BUMP

[HAND HERPES]

I'm not smart with cars but I'd say a fuel issue since your getting on it, it can't supply enough fuel (weak pump??). Could be the Opti or ignition related too??

[popo8]

Lets start with with the most obvious signs of a problem...is the SES light coming on at all? If not, have u scanned the car anyways...because even without an ses light there could be trouble codes... Now...assuming no codes verified by scanning it....

Lets move o to the three basic things for an engine to run...air , fuel and spark....

Air is hard to get wrong unless u have physically restricted the intake....

FUEL: START by checking fuel pressure at the rail and see if u are getting proper psi (43psi @ idle iirc) if not we can trouble shoot from there.

Spark....have u done plugs and wires i it recently...how are the wires...age and mileage of the opti...what coil?

I. On my cell so i cant aee if ur signature has ur vehicle info... But if not...set it up so we have a starting point


Larry (Popo8) Co-owner
LTXtech.com

[dansformula]

well I have an msd distributor at least the cap and rotor not sure if the opti itself if msd or not. msd coil. and msd wires with ngk plugs. fuel rail is fine but my quick connect is fuzzed up. I broke the clip inside so it is rigged on for now (cant find fuel quick connect clips any where) but there is no leaks. I will take it by autozone and get the codes scanned tomorrow. But from what I know today when i had the MAF sensor connected the car ran rough idk if the sensor is bad or dirty or if there is an o2 problem but I would think it would run rough constantly. ill check fuel pressure tomorrow as well.

[dansformula]

I'm not smart with cars but I'd say a fuel issue since your getting on it, it can't supply enough fuel (weak pump??). Could be the Opti or ignition related too??

well I was thinking the same but I can get on the car all I want but when I let off and cruise it'll start to misfire then

[popo8]

Post up results from fuel pressure... and codes , and we can work from there.