Crappy idle...findings.....UPDATE!!!

S

SY2767

Member
I just recently purchased a sy with 134xxx miles that had a misfire at idle. I purchased (but have not installed yet) new msd wires, ngk ur5 plugs, cap and rotor, oxy sensor, fuel filter and a gm coil (it has a accell coil on it now), i have also removed all the vacuum lines and will be installing new ones. The plugs i removed were as new with a nice tan color but they were gaped at 37 and one was gaped at approx 25 !!!!!, the cap and rotor were full of carbon buildup and the wires were burned to the plugs on a couple, 2 of them were broken, one at the cap and the other at the plug. The vacuum lines were shot! Very dry rotted in a couple of places and loose in a few more. Are their any vacuum lines that have to be hard lines( as stock plastic) or can i change tham all to rubber?
 
Last edited:
Ty0279

Ty0279

Historically Significant
Re: Crappy idle...findings.....

Re: Crappy idle...findings.....

You can go w/ all rubber. Keep the hard plastic t-fittings though. Make sure you keep them away from heat, and zip-tie them nice and tight.

While you're at it, you should go ahead an run a compression test on your Sy (if you haven't done so already).
2cents.gif
 
gjp

gjp

another post whore
Re: Crappy idle...findings.....

Re: Crappy idle...findings.....

I would change the lines to silicone. I found a good kit on e-bay. Its about 35$ but the silicone lines are thick. The silicone lines I got from pep boys sucked. MSD makes a nice stock style coil for our trucks too. I had good luck with a 32-34 gap with my truck stock with the UR5's
X2 on the compression test.
 
Flyin Ryan

Flyin Ryan

hated cuz he drives fords
Re: Crappy idle...findings.....

Re: Crappy idle...findings.....

wow sounds like a miss fire at idle was good for all the issues it had.. bet it helped with the purchase price though :)

anyways i'd replace all vacuum lines with silicone lines.. I used lines from http://www.bakerprecision.com/hosetech.htm which are really thick and of the best quality i've seen so far for vac line wihtout a doubt.
 
SY2932

SY2932

Administrator
Re: Crappy idle...findings.....

Re: Crappy idle...findings.....

Since you are new to turbos, don't forget about the check valves that are on the vacuum lines. They keep items from getting "pressurized" when you're in boost...
 
S

SY2767

Member
Re: Crappy idle...findings.....UPDATE!!!

Well i took the TB off tonight for a check and good cleaning and found 3 more things. I unscrewed the IAC with my hand !! and the part on the bottom of the TB that coolant flows through( it has been bypassed on my truck) was also on hand tight, there was also a vac line fitting with nothing attached to it. (i didn't know there was one under there!!) While it was apart i sprayed some seafoam inside the intake and also cleaned the TB with it until everything was super clean. I'm not sure if the cleaning and such will help as i won't be starting the truck until tomorrow..........
 
TYRODD

TYRODD

My ass. Look at it.
Re: Crappy idle...findings.....UPDATE!!!

250rtone said:
Well i took the TB off tonight for a check and good cleaning and found 3 more things. I unscrewed the IAC with my hand !! and the part on the bottom of the TB that coolant flows through( it has been bypassed on my truck) was also on hand tight, there was also a vac line fitting with nothing attached to it. (i didn't know there was one under there!!) While it was apart i sprayed some seafoam inside the intake and also cleaned the TB with it until everything was super clean. I'm not sure if the cleaning and such will help as i won't be starting the truck until tomorrow..........
Click to expand...

The coolant fittings under the TB were never used on our trucks.

The 1/16" nipple on the underside of the TB goes to the charcoal canister for emission purposes, thats the black cylinder below the factory airbox/drivers side headlight. ;) ..there is supposed to be a check valve on that vacuum line.
 
S

SY2767

Member
Re: Crappy idle...findings.....UPDATE!!!

TYRODD said:
The coolant fittings under the TB were never used on our trucks.

The 1/16" nipple on the underside of the TB goes to the charcoal canister for emission purposes, thats the black cylinder below the factory airbox/drivers side headlight. ;) ..there is supposed to be a check valve on that vacuum line.
Click to expand...

Thanks, that changes a few things...
 
You must log in or register to reply here.
Top