Stumble problem + Air Cleaner ? hehe...
For some reason I have developed a stumbling problem on startup sometimes. I'll get to that in a minute. When I first got the truck, it had a wierd idle on start-up. I decided last summer to finally do something about it and replaced the IAC, TPS, and cleaned the throttle body. Still no luck. I found a vaccum leak beacuse in the engine compartment it would go PSSSS PSSSSS PSSSS at idle. I fixed the like 2 inch section of hose that connects two plastic sections of hose over by the PCM about a month ago. Right well... i've always been cool with the wierd idle on startup. It would start up, the rpm gauge would gradually dip, truck would shake, and rev to compensate. Would do that maybe 3 times and that was it. My MPG have dropped and I don't believe it to be a plenum (I'm 3 hours away or i'd check). Now onto the stumble problem. It seems that if I start the truck after its been warmed up, sometimes it stumbles real bad, and then it will start up. As a matter a fact last week when I put some gas in it. I turned the key at the pump and all I hear is crank crank crank. turn key off and turn it back on and its stumbles bad and once it gets to idle, theres never another problem. No drivability problems, no other signs or symptoms. Just seems on a warm start, she will sometimes act up. I'm leaning towards o2's since theres not a problem @ cold start-up related to this stumbling. Fuel pump kicks in every time. Just kinda curious for the most part. I won't be home for like another three weeks, so .... any guesses would be sufficient at this point. Cap, rotor, wires, plugs, etc.. all done last summer. Stumbling started for the first time maybe 3 months ago. I'm at college and don't go home often enough so thats why there is such a big gap. When it happened the first time, I blamed it on bad gas. It doesnt seem like she starts up and revs anymore. just kinda turn key crank crank stumble stumble graduale raise in idle idle. not like. crank crank rrrroooommmm.
Thanks in advance
Thanks in advance
I had a 2000 2wd 318. It would do that at start up. I tried all sorts of things... Never helped. As for the stumbling i wouldnt the slightist. It could be any number of this.. and i wouldnt want to start pointin fingers. Maybe a tech guy could throw some input in.
I take it there are no leaks anywhere. I would be thinkin it is a fuel problem.Your pump is good or your problems would be different.If this was 1970 I would be looking at the automatic choke.
Run the standard fuel tests. Check clogs, etc. If you got a Chilton or Hayes manual it can guide you through check your system.
Jeff
Old enough to have installed manual choke cable.
No leaks, no nothing. Truck runs fine. It's just on a warm start, sometimes she will just stumble and stumble.. then get toidle. then it will all be ok. I can't find or hear vaccum leaks. Guess ill get a friend to take a vid or something and ill post back up when i get it.



