Idling question updated

Jake11 · Dec 20th, 2005, 02:04 PM

Posted in here a while back on truck not idling, here is the update.Had the truck on a scanner, it is doing wierd things, it has gotten now when it gets run for a while and I guess the engine compartment gets hot it starts running bad. Surges, seems to have a loss of power, valves pinging worse. Won't idle also, My friend had the scanner on it the other day at his house and caught it in one of the spells. The gram per second went to 54 on the mass air flow sensor. We unplugged the mass air flow sensor and it set the service engine light immediately. The 02 sensor on the front shows it running rich for periods of time th en running lean for periods of time. WE unplugged the main 02 sensor and it did not set a service light, he said the scanner showed the back 02 sensor was doing absolutely nothing, showed no response at all. There was some reading, don't remember what it was that showed a negative 10.4, he said that was not normal and when we unplugged the mass air flow sensor it did not change that reading. He might have said something about a rail or something on that reading, maybe fuel was mentioned also, not sure on the -10.4 reading exactly what it was.I know it was not fuel pressure though. Trying to find a used Mass air flow sensor, tried the local salvage yards here but still no luck, a new one is 400.00 bucks and not entirely sure that is what it is.What would be your best guess, and would you know a place that might have a used mass air flow sensor if you think that sounds like a reasonable part to replace?
Still have not ruled out computer, that is why I hate to buy a new 02 sensor and that not be it. Friend of mine called a guy he knows at nissan who has been a mechanic there for 15 years, he said he would start with 02 sensor and go from there. Anyone know of a place I might locate a used mass air flow sensor for this truck?
Thanks

79kz400 · Dec 21st, 2005, 05:54 PM

Checked all your ground leads?

spat · Dec 24th, 2005, 06:32 PM

Quote:

Originally Posted by Jake11

Posted in here a while back on truck not idling, here is the update.Had the truck on a scanner, it is doing wierd things, it has gotten now when it gets run for a while and I guess the engine compartment gets hot it starts running bad. Surges, seems to have a loss of power, valves pinging worse. Won't idle also, My friend had the scanner on it the other day at his house and caught it in one of the spells. The gram per second went to 54 on the mass air flow sensor. We unplugged the mass air flow sensor and it set the service engine light immediately. The 02 sensor on the front shows it running rich for periods of time th en running lean for periods of time. WE unplugged the main 02 sensor and it did not set a service light, he said the scanner showed the back 02 sensor was doing absolutely nothing, showed no response at all. There was some reading, don't remember what it was that showed a negative 10.4, he said that was not normal and when we unplugged the mass air flow sensor it did not change that reading. He might have said something about a rail or something on that reading, maybe fuel was mentioned also, not sure on the -10.4 reading exactly what it was.I know it was not fuel pressure though. Trying to find a used Mass air flow sensor, tried the local salvage yards here but still no luck, a new one is 400.00 bucks and not entirely sure that is what it is.What would be your best guess, and would you know a place that might have a used mass air flow sensor if you think that sounds like a reasonable part to replace?
Still have not ruled out computer, that is why I hate to buy a new 02 sensor and that not be it. Friend of mine called a guy he knows at nissan who has been a mechanic there for 15 years, he said he would start with 02 sensor and go from there. Anyone know of a place I might locate a used mass air flow sensor for this truck?
Thanks

Does your friends scanner have "freez frame data"? If so and he printed it out send it to me and I will analyz it for you.