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Discussion Starter #1
i posted about my new suburban having a low cylinder a week ago or so. i just went and bought a new 18" open car trailer and on the way home, the truck seemed to be running rougher. now it could have been the trailer pulling against the truck and the trailer was empty, but it seemed like a more pronounced miss. is it possible that this cylinder is farther gone than previously hoped?

i also found out that my hitch plug on the back doesnt work properly so i'll have to dig around in there too. :(
 

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i posted about my new suburban having a low cylinder a week ago or so. i just went and bought a new 18" open car trailer and on the way home, the truck seemed to be running rougher. now it could have been the trailer pulling against the truck and the trailer was empty, but it seemed like a more pronounced miss. is it possible that this cylinder is farther gone than previously hoped?

i also found out that my hitch plug on the back doesnt work properly so i'll have to dig around in there too. :(
18” car hauler, what are you hauling matchbox cars?

Sorry I just couldn’t resist.

I missed what you got for compression on your tests, if was real low it could be the problem as could a bad plug wire, or plug.

The wiring problem can be tough, this site can be of some help.

http://www.etrailer.com/faq/wiring.aspx

The easiest and quickest way would be to put in a new connector that just plugs into the original harness.

http://www.etrailer.com/c-VWH.htm
 

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Discussion Starter #3
cylinder 1-7 was around 90ish and cylinder 8 was 75 or so. there is a slight miss at idle while in drive but im thinking it is because the revs are so low you can feel it real good.

i put 18' first but it didnt look right so i used the other notation. ;) the guy at the trailer shop said that he would put a new plug on it first to see if that fixes it cause it could be some corrosion at the back of the plug or the like.
 

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cylinder 1-7 was around 90ish and cylinder 8 was 75 or so. there is a slight miss at idle while in drive but im thinking it is because the revs are so low you can feel it real good.

i put 18' first but it didnt look right so i used the other notation. ;) the guy at the trailer shop said that he would put a new plug on it first to see if that fixes it cause it could be some corrosion at the back of the plug or the like.
Make sure the new plug has a cap on it so when it’s not in use to keep it from getting all grungey all over again.
 

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Most mechanics say 15 psi difference is where the problem gets noticeable, factory repair manuals usually call for a rebuild at this point. I've had bigger spreads than that on engines with a small miss like yours and run them for a long time.
Try a tune-up, check the plug wires, and some injector cleaner, maybe even some auto tranny fluid in the oil a few miles before the next oil change, this'll clean out some of the build-up in the lifters and help the valves a little if your loosing compression through the intake or exhaust.
If your gonna tow the loaded trailer a lot it may be time to source a remanned long block or a rebuilder engine to have in case. I'd say at this point you have time to get everything ready so it doesnt end up a crises when it gets to sick to continue.
 

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Most mechanics say 15 psi difference is where the problem gets noticeable, factory repair manuals usually call for a rebuild at this point. I've had bigger spreads than that on engines with a small miss like yours and run them for a long time.
Try a tune-up, check the plug wires, and some injector cleaner, maybe even some auto tranny fluid in the oil a few miles before the next oil change, this'll clean out some of the build-up in the lifters and help the valves a little if your loosing compression through the intake or exhaust.
If your gonna tow the loaded trailer a lot it may be time to source a remanned long block or a rebuilder engine to have in case. I'd say at this point you have time to get everything ready so it doesnt end up a crises when it gets to sick to continue.
Great advice!!!:great:
 

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Discussion Starter #7
im going to be getting a brake controller in the near future. my truck is a 96 but it came from the factory with the HD towing package. should i have a connector under the dash for "plug and play" operation or will i have to wire it up manually? i see a bluish connector almost right under the steering wheel at the bottom of the dash but i haven't looked at it closely yet.
 

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Discussion Starter #8
bump for my question above as well as an update on the truck running rougher with the trailer in tow. today i helped my boss haul a coke machine to our office and the truck felt pretty good with a little weight on the trailer. runs much better than with an empty trailer. i also put it in 3rd instead of overdrive about halfway to the office and it felt a even better as well. good times all around.
 

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Could be trany, if it is running and hauling just fine in drive and not when it is in overdrive.

PS

You are not supposed to haul in overdrive anyway.

The trany trys to shift to much. Unless of course you are driving on flat level roads doing 80+ MPH.

That also is not recommended.
 
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