joecool108

91 Vert 5.0 Liter TBI, just started having issues. As I am cruising down the road at no particular speed, with my foot steady on the accellerator, running smoothly, the car wants to momentarily sputter and cut off, but within 2 seconds, its back to running again. Almost similar to if you had turned the key off and back on again. Not sure if it could be igntion module or fuel related. Only seems to be happen while driving, doesnt happen at idle. Any ideas?

Rolling Thunder

Have you tried checking your fuel pressure? Make sure it holds steady in the higher RPMs. Was the tach acting up when this happened?

Atilla the Fun

I had this happen to my '88 LO3. It's maddening. Since an LO3 is not a fun engine, even when running perfectly, I didn't solve the problem. Instead I swapped in a carbureted 350.

joecool108

Didnt really notice the tach because it doesnt happen at a specific time, just seems to be random, maybe 2 or 3 times daily. I put a can of seafoam in it to see if that may help. Ill check the FP, but it doesnt seem to do it in park, just wile driving. I was thinking maybe ignition module?

Rolling Thunder

It could be the ignition module but usually when they fail you also notice the tach going a little crazy as it is driven by the ignition module. The way i see it it could be fuel or the ignition. You can test the fuel pressure at a high RPM (in part) to kinda simulate driving condition. In reality actually driving it requires more fuel but if it cant maintain fuel pressure in park at a higher RPM then it will never be able to keep up under actual driving conditions. Next i would check the injectors (ohm them out check for leaks all that good stuff). For the ignition, besides connections and stuff of that nature, there's not a lot of stuff that will act up intermittently. I mean sure anythings possable i suppose but at this point i don't really suspect anything out of the norm. The Ignition control module is a part that can act up intermittently and usually when hot as well. You may want to just try and replace it if we don't find any fuel issues first. They can test them but if it does have an intermittent problem chances are it will test good.

joecool108

Ok, tach does drop when the sputter happens, it did it today on the way home from work twice. I also notice that when i have the cruise control on, it does not happen, only happens when I seem to be accellerating.. Ideas?
TPS? Ignition Module?

Rolling Thunder

Well what happens when you just floor it like your trying to accelerate quickly? If it only happens on acceleration thats a different story.

joecool108

Doesnt seem to happen when I floor it, but it does happen when I am accellerating normally.

joecool108

Update, problem is very erratic. sometimes it will happen 3 or 4 times on a trip from home to work (about 30 miles) sometimes wont happen at all. Tach does drop when car sputters. Car is driven under a normal load and seems to happen after I try to accellerate (doesnt seem to happen when pedal is floored, seems to happen under normal accelleration