random stalling issue

[Gryphon313]

**Update**

Haven’t had a stall since I pulled the a/c clutch fuse. I wanted to give it a couple days of driving in the conditions that would routinely result in a stall before I reported back.

So, for now I have eliminated the stalling issue, but I will need to investigate the reason that the a/c was causing the truck to stall. I have two theories… first one involves the a/c system having a problem, the other involves the Russians…

 

[red_mr2]

**Update**

Haven’t had a stall since I pulled the a/c clutch fuse. I wanted to give it a couple days of driving in the conditions that would routinely result in a stall before I reported back.

So, for now I have eliminated the stalling issue, but I will need to investigate the reason that the a/c was causing the truck to stall. I have two theories… first one involves the a/c system having a problem, the other involves the Russians…

so you think it might be your AC clutch? i actually moved a few relays around and so far no stalling also. i replaced the fuel pump relay (not the fuse 27) and so far no stalling. i havent been using the AC though since its been fresh so im not sure if it could also be the AC compressor.

 

[pat247]

**Update**

Haven’t had a stall since I pulled the a/c clutch fuse. I wanted to give it a couple days of driving in the conditions that would routinely result in a stall before I reported back.

So, for now I have eliminated the stalling issue, but I will need to investigate the reason that the a/c was causing the truck to stall. I have two theories… first one involves the a/c system having a problem, the other involves the Russians…

News flash: All AC compressors put a load on the engine, if it causes the engine to stall it is generally in the tune. Both of you have mentioned your ac works fine.

 

[Gryphon313]

so you think it might be your AC clutch? i actually moved a few relays around and so far no stalling also. i replaced the fuel pump relay (not the fuse 27) and so far no stalling. i havent been using the AC though since its been fresh so im not sure if it could also be the AC compressor.

Not sure that it is the clutch per se, but with the a/c clutch doing it’s thing, my truck will stall after the 3rd or 4th on/off cycle (at idle). I pulled the fuse so that I could keep the a/c compressor from cycling while I have the hvac set to defrost. Kinda need defrost around here this time of year.

As far as what’s causing the additional load on the engine, dunno… Could be that the power steering pump is dragging and the a/c is the proverbial “straw that broke the camel’s back.” I had a bad idler pulley, but it wasn’t so far gone that it would cause stalling. And, as suggested, it could be that the pcm is not compensating for the additional load of the a/c compressor at idle.

All I know is that the truck is much happier without the a/c compressor kicking on and off. I found a local mechanic with a good rep, so I will probably have him take a look at the truck in the near future.

 

[Gryphon313]

News flash: All AC compressors put a load on the engine, if it causes the engine to stall it is generally in the tune. Both of you have mentioned your ac works fine.

Unfortunately, at this point I have no idea if this truck is running the factory tune or an aftermarket tune. It’s on my list of things to look into as I get through the maintenance checklist. Like I’ve said all along, the lack of DTC’s has been frustrating, but also maybe points to something outside of the pcm’s purview. I feel like these trucks are usually pretty good at telling you what’s wrong.

 

[red_mr2]

update: the truck has not stalled since 10/27/2022 and the date today is 11/10/2022. The only thing i did to the truck since that day was change out the fuel relay (not fuse 27) and fix the iwe vacuum lines that were damaged. drove the truck for 2hrs the other day in stop and go traffic and in the rain and did no stall out once. im not sure if its "fixed" but usually by now it would have stalled a few times atleast. any luck on your end @Gryphon313

 

[Gryphon313]

update: the truck has not stalled since 10/27/2022 and the date today is 11/10/2022. The only thing i did to the truck since that day was change out the fuel relay (not fuse 27) and fix the iwe vacuum lines that were damaged. drove the truck for 2hrs the other day in stop and go traffic and in the rain and did no stall out once. im not sure if its "fixed" but usually by now it would have stalled a few times atleast. any luck on your end @Gryphon313

I have not stalled since pulling the a/c clutch fuse. Once I get the Lee Power Steering kit installed, I will replace the a/c clutch fuse and try to determine if the excessive drag was being created by the a/c compressor or power steering pump.

I have also replaced all of the IWE hoses, as well as, the manifold vacuum supply line. The issue with my truck may have been a “sum of all parts” kinda thing rather than one single culprit. Only thing that matters is that it is no longer stalling.

 

[thecigardon]

so you think it might be your AC clutch? i actually moved a few relays around and so far no stalling also. i replaced the fuel pump relay (not the fuse 27) and so far no stalling. i havent been using the AC though since its been fresh so im not sure if it could also be the AC compressor.

Which relay position is it if it’s not the fuse 27? Sorry, I’m a newb. Lol

 

[thecigardon]

I have not stalled since pulling the a/c clutch fuse. Once I get the Lee Power Steering kit installed, I will replace the a/c clutch fuse and try to determine if the excessive drag was being created by the a/c compressor or power steering pump.

I have also replaced all of the IWE hoses, as well as, the manifold vacuum supply line. The issue with my truck may have been a “sum of all parts” kinda thing rather than one single culprit. Only thing that matters is that it is no longer stalling.

Did this end up resolving everything? Unfortunately been in the same position but pulled 10a for the ac clutch and it hasn’t stalled since. Still gets low IMO on idle but no stalls in 3 days.

 

[Gryphon313]

Did this end up resolving everything? Unfortunately been in the same position but pulled 10a for the ac clutch and it hasn’t stalled since. Still gets low IMO on idle but no stalls in 3 days.

It was more of a band-aid that let me keep driving my truck. Ultimately, I replaced both upstream O2 sensors and that, in combination with a new canister purge valve, resolved the stalling.