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I changed my fuel filters last night and now my truck has a rough idle/miss to it. I followed the instructions and even primed the system (3) times before starting the truck. The only thing I didn't have was a torque wrench, but I was trying to be very careful. Could this be caused by overtightening the caps? Or even under torqued?
Check the cap on the lower filter, there should not be any gap between the filter cap and the housing, if there is you will suck air and the truck will run rough and miss.
Toolman - I was checking for that as sort of gage to make sure it was seated. The truck started fine and as I crawled back under to look for leaks (none) on the lower filter, that is when the truck started to miss. When priming the fuel system, I probably only waited 5-10 seconds between cycles? could the problem just be air trapped in the system yet?
yes left over air could be the problem. a torque wrench is not required to chang fuel filters. you just have to make sure that the threads on the caps are clean and lube the o rings with oil or a light grease or petroleum gelly, not fuel and make sure the flanges meet. Good luck
When changing the fuel filters I look for the following:
1. Use OEM filters.
2. Change the filter o-rings and lubricate them with engine oil.
3. Snap the filter into the cap and install it into the housing.
4. Tighten the filter so that there is no gap between the filter cap and the filter housing. You will feel resistance when the o-ring begins to seat, but if the o-ring was properly lubricated it will allow you to fully tighten the cap.
If the truck runs rough after filter replacement, the filter is not properly tightened or the o-ring is likely cut.
The tech folder has excellent fuel filter replacement instructions that are far better than the above.
You're not alone with this; I had the same issue. I pulled it all apart, checked, threads, o-rings, etc, reinstalled EXACTLY as I had the first time and had no issues. I don't know the issue, but making sure the caps are seated is key. Listen to all of these guys and use the tech folder are my best recommendations for you. Good luck.
If I remember correctly you get new o rings with the filters. Just a thought here I was told a long time ago to NEVER use petroleum jelly on o rings as it can make them swell up.