Revisit: Idle problem

From : fawilson

Q: when its cold it idles ok and sometimes when it is warm it will slowly raise the idle rpm and slowly fade back to normal. i can not really call it a rumble surge or loping. i can call it irritating. the fact that its only happening when warm is an important indicator - this seems to suggest that its only idling improperly when in closed loop mode. there are two modes of operation on a fuel-injected vehicle open-loop and closed-loop. when in open-loop mode the computer determines the amount of fuel to inject based on a fixed table called a fuel map based on several inputs the map sensor the tps the temp. sensor etc. in closed-loop mode the computer still uses those input as a suggestion of how much fuel to inject but relies on feedback from the oxygen sensors to adjust the fuel mixture up or down attempting to maintain a specific air/fuel ratio. since youre saying the idle only gets erratic when the engine has warmed up id suspect a faulty oxygen sensor. if i had a scan tool capable of displaying oxygen sensor outputs id use that to confirm these suspicions. id be somewhat leery of simply throwing an oxygen sensor or two depending on your specific vehicle because of the cost anywhere between $50 and $100. however this was exactly the problem with a friends 00 durango recently... erratic idling when warm stumbling during cruise cleared up when he floored the throttle - that also puts the engine back into open-loop mode etc. even though there were no codes set it was the oxygen sensor that was the culprit. after changing that out his problems were solved. .

Replies:

From : tom lawrence

its an odd mix of equipment all geared towards farm outdoor and the small excavator. they deal in kubota who doesnt have an accurate time guide mahindra deere lawn products dixie choppers and suzuki motorcycles and four wheelers. deere has a pretty decent time guide but theyve been in the business a bit longer than kubota. im not sure where mahindra stands on it. currently they have one tech who is leaving for a job with the local government one tech who has a clock over his head see it and the shop owner who is moving up to the jobs he should be attending as shop owner. -- max everyone is entitled to his own opinion he is not entitled to his own facts. sen. daniel patrick moynihan of new york thanks for the info denny. ill get your email if i have more questions after we get into the discussions on how to set this up. the one thing running against the techs at this point is at least one of the manufacturers doesnt have an accurate flat rate book. fortunately the management is aware of this so were in the process of doing time studies on everything that comes through. just out of curiosity what kind of dealer is this automotive ive never run into a manufacturer that didnt have a warrenty time guide. it doesnt really matter if its accurate or not its the time they go by. sometimes you can get a little extra on certain lops if you have really good cause and accurate time stamps denny .

From : fawilson

theres definitely up - down movement that shouldnt be there. ill go to the local body shop i have do my work and see what they say. thanks ken you can try to loosen up the hinges jacking the door up to the correct height and tightening them back down but in many cases this indicates that the hinges are just worn out and need to be either rebuilt or replaced. -- if at first you dont succeed youre not cut out for skydiving the drivers door on my 97 dakota is sagging. what is the best way to fix this thanks ken .