Author Topic: running rough after towing?  (Read 8505 times)

Offline 2502

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running rough after towing?
« on: April 02, 2010, 10:53:53 am »
i towed my other pickup wtih my burban on tuesday, now it doesn't seem to be running the same. at idle it runs kinda harder, i can feel more of a shake or vibration, and it sounds kinda like sputtering i would say. not sure how to describe that. changed the cap, rotor, and plugs, they all needed replacing, and it ran ok for a few minutes to drive around the block so i thought ok problem solved. not when i started it back up to head home for the night. i don't know if this is considered a "misfire" or not but that's what i'm guessing it is. but it only happened after towing, and it doesn't run so rough when it's in park. the second i put it in gear, it starts up. any suggestions?

Offline Lt.Del

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Re: running rough after towing?
« Reply #1 on: April 02, 2010, 11:38:43 am »
how 'bout a little info on the 'burb...year, Tbi, carb, etc...?

checked all vacuum lines?   Is the distributor hold down clamp tight...not causing the distr. to turn any?  Check fuel filter?

Offline VileZambonie

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Re: running rough after towing?
« Reply #2 on: April 02, 2010, 11:56:25 am »
Yes, need more info. Make sure the EGR isn't hanging open
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Offline zieg85

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Re: running rough after towing?
« Reply #3 on: April 02, 2010, 12:08:08 pm »
From the pictures on the other post it is TBI at the very least
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Offline Stewart G Griffin

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Re: running rough after towing?
« Reply #4 on: April 02, 2010, 02:20:58 pm »
You're talking about the suburban?

If so, i wouldn't worry about for a while---my cavalier(also TBI) runs strange after i drive with several friends in the car;  Apparently the car is very sensitive to more weight than it usually carries.

That's just my opinion.

Offline 2502

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Re: running rough after towing?
« Reply #5 on: April 02, 2010, 02:22:42 pm »
it's a nagging concern i want to address right away. it's tbi, it's a 1995. 350, 239k miles. i was gonna check the egr if it has one, and replace the fuel filter at least. not sure what else to check...

Offline Lt.Del

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Re: running rough after towing?
« Reply #6 on: April 02, 2010, 03:40:52 pm »
do this when it idles rough or differently, push down on the TBI  injectors one at a time and see if the flow of gas changes.

I thought i had ignition problems one time and realized that the flow of gas wasn't right in my '91 suburban and she wouldn't run right on sporadic occasions.   I had to replace the plastic clip thing in the TBI....


http://forum.73-87chevytrucks.com/smforum/index.php?topic=5280.msg25446;topicseen#msg25446

Offline 2502

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Re: running rough after towing?
« Reply #7 on: April 02, 2010, 04:48:14 pm »
which is which? wanna show a dummy a pic? i'm gonna replace the wires, not that i think that'll solve the issue, but i did everything else so may as well.

Offline Lt.Del

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Re: running rough after towing?
« Reply #8 on: April 02, 2010, 04:55:52 pm »
this is just a stab, but it worked for me.  One day while troubleshooting, I happened to notice while it was "trying" to idle, only one of the two injectors were putting gas down the throttle body.  The entire right bank had no gas flow. She was running on a bout 4 cylinders.  I pushed down on the plastic part (with the two wires going to it) and she ran smoothly.  Went to a salvage yard and yanked about 3 or 4 of those things off of old engines.  Spliced it in, that was the trick.



Vile also, as aways, may be on to something as well.  It could be carbon build up in the EGR after having to heavy foot it for a while while towing.   Cat could also be clogged with carbon, but it usually wouldn't effect idle, only under acceleration.

Offline 2502

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Re: running rough after towing?
« Reply #9 on: April 02, 2010, 06:48:26 pm »
this is just a stab, but it worked for me.  One day while troubleshooting, I happened to notice while it was "trying" to idle, only one of the two injectors were putting gas down the throttle body.  The entire right bank had no gas flow. She was running on a bout 4 cylinders.  I pushed down on the plastic part (with the two wires going to it) and she ran smoothly.  Went to a salvage yard and yanked about 3 or 4 of those things off of old engines.  Spliced it in, that was the trick.



Vile also, as aways, may be on to something as well.  It could be carbon build up in the EGR after having to heavy foot it for a while while towing.   Cat could also be clogged with carbon, but it usually wouldn't effect idle, only under acceleration.
it's mainly under acceleration in lower rpm range. it just doesn't seem to have the power.


so do i replace teh egr? friend of mine said clean it out, and i dont even know what it looks like.

Offline 2502

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Re: running rough after towing?
« Reply #10 on: April 03, 2010, 01:35:13 am »
ok so, i replaced the wires. ran it for a test, didn't seem to solve the issue. ran to a friend's house for a bbq, and the thing is running just fine now.  ::)

Offline VileZambonie

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Re: running rough after towing?
« Reply #11 on: April 03, 2010, 06:00:21 am »
EGR is probably sticking open a little bit. If it does it again pull the vacuum hose off the egr valve and see if there's vacuum there.
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Offline 2502

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Re: running rough after towing?
« Reply #12 on: April 03, 2010, 06:50:13 am »
EGR is probably sticking open a little bit. If it does it again pull the vacuum hose off the egr valve and see if there's vacuum there.
thanks i'll be checking both if it starts actingup again

Offline Stewart G Griffin

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Re: running rough after towing?
« Reply #13 on: April 03, 2010, 04:49:35 pm »
Like i said, i think tbi vehicles can run wierd for while after being subjected to more than normal weight.

That is just my opinion though.

Offline Irish_Alley

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Re: running rough after towing?
« Reply #14 on: April 04, 2010, 02:13:31 am »
stew if that was the case i don't think California would let anyone tow anything, it would be a tow free state due to the improper emissions of vehicles while under a load.
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