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Idle/Driving problems after H/I/Blower install

  • Thread starter Thread starter HuebyStang94
  • Start date Start date May 26, 2005

HuebyStang94

New Member
Aug 25, 2004
133
0
0
STL
May 26, 2005
#1
  • May 26, 2005
  • #1
Hey all, I just recently installed ALL the parts in my signature. I now have a couple of problems, if anyone could provide some help/thoughts I would appreciate it!

1. I can get the car to idle around 950-1000 rpms with the base timing set to 0*-10* with the SPOUT out (i'm still using the stock cam).

2. I can't get the car to idle with the base set at 6-10* with SPOUT in. It won't even turn over.

3. I can't get the car into drive (auto) without it dying, UNLESS I get the idle up to 1500, so when the rpms drop into gear it's around 1000-1100 rpms, and the timing set around 0-4*, and then it still bucks a lot.

Fuel pressure with Vac in is 41#, TPS is around 1.02V, Vacuum is around -20. I've spent a lot of time on stangtuning.com playing with the PMS (adding idle fuel %, subracting idle time, etc.), but no luck.

I'm beginning to wonder if this could be caused by my Roller Rockers (pedestal mount) not being properly installed? Could they be on too tight and causeing the valves to not fulley close, and cause rough/no idle? (It was the first time I did a RR install, and didn't use any shims / used stock pushrods.......)

Could this be a IAC problem maybe too? Any ideas to help me out would be appreciated!!!!
 

Numbles

Active Member
Dec 10, 2003
998
0
36
Chicago, IL
May 26, 2005
#2
  • May 26, 2005
  • #2
Set the timing at 10* base with the spout out. And try running without the PMS.

EDIT: Do you think you installed the spark plug wires right. Maybe 2 are off. The hight idle with the base timing at 10* with the spout out suggests vacuum leak maybe but you have shecked into that.

TTT far ya.

For RR install Did you tighten them till the pushrod couldn't move up and down. And then turn a half turn. I think its a half turn(off the top of my head). And lock them in. If so that probably not your problem.

Also pull you plugs and see what they look like.
 

HuebyStang94

New Member
Aug 25, 2004
133
0
0
STL
May 26, 2005
#3
  • May 26, 2005
  • #3
Thanks for the reply. When I try to set the timing up to 10* with SPOUT out, it starts to die on me. I can get it kinda close, but I'm adding 2-4% idle fuel too. (cause upping the idle is leaning it out, correct?)

I'll re-check my plugs too, but I have done that once... thanks!

I pulled my plugs at one time and they looks brand new still....... I'll have to pull them again.

As far as the pedestal RR install........ I pretty much torqued them down to 18 ft. lbs. and maybe a little more where there was still play.
 

Numbles

Active Member
Dec 10, 2003
998
0
36
Chicago, IL
May 26, 2005
#4
  • May 26, 2005
  • #4
Is your PMS new or used?
 

BlackFox5.0

Founding Member
Aug 7, 2000
3,514
1
0
Massachusetts
May 26, 2005
#5
  • May 26, 2005
  • #5
I had the same problem when I had a blower, the only thing that fixed it was my Tweecer. If I loaded a stock tune the car wouldn't even run. Get tuning on that thing. I dont know how PMS works compared to Tweecer, but after I loaded my injector size MAF transfer, and some other things to let the computer know I made changes, it ran like stock.

This probably doesn't help you, lol

BTW, being too rich at idle will cause stumbling, it should be 14.7afr, except when cold at the first 120seconds after startup.
 

Numbles

Active Member
Dec 10, 2003
998
0
36
Chicago, IL
May 26, 2005
#6
  • May 26, 2005
  • #6
From the sounds of it its probally the IAC. At 10* with the spout out you should have no problem idling with the stock tune and cam.

Go over maf and the air temp sensor connections as well.
 

HuebyStang94

New Member
Aug 25, 2004
133
0
0
STL
May 26, 2005
#7
  • May 26, 2005
  • #7
Thanks guys.. yes the PMS is brand new, with Rick Anderson "start up" tune already in place. Maybe taking out some fuel at idle will help, and replacing the IAC? The MAF and air temp sensor has been cleaned......
 

Numbles

Active Member
Dec 10, 2003
998
0
36
Chicago, IL
May 26, 2005
#8
  • May 26, 2005
  • #8
BTW set your FP at 40 or 41 psi with the vacuum off. This will drop the psi to about 35 when idling. You can tune the extra fuel in with the PMS. Might help. And check the MAF element to make sure you didn't damage it. Did you use a q-tip and rubbing alchahol. Ive broken one before and my car had a hell of a time running when I put it back on the car.

Also. I dont this rick would mess up with a start up tune but start the car without the PMS and see what happens. Maybe he changed sumething to a greater extent then he should have on accident. This way you can rule out the PMS.
 

HuebyStang94

New Member
Aug 25, 2004
133
0
0
STL
May 29, 2005
#9
  • May 29, 2005
  • #9
WOOHOO! Finally........ after re-doing all my RRs... and playing with the timing a little more, it's idling right. Now it idles at 900 just fine.. and in gear it will idle down at 700 without a problem.

It just started to rain, so I can't drive it much yet, but it feels 1000% better.... Now time to get it to a dyno.

-- One thing, every so often it will puff out some white "mist".. it doesn't stay and linger like smoke, it goes away quickly, but seems to stay consistent... ideas?
 

BlackFox5.0

Founding Member
Aug 7, 2000
3,514
1
0
Massachusetts
May 29, 2005
#10
  • May 29, 2005
  • #10
Sounds like condensation in the pipes. not really avoidable, just dont worry about it unless your radiator overflow starts gushing like Ol' Faithful
 
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