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Engine Stock TB - smoke test - leaking bad

  • Thread starter Thread starter R82148V
  • Start date Start date May 18, 2025
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Jarhead67

5 Year Member
Nov 24, 2018
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Windsor Locks, Connecticut
May 24, 2025
#21
  • May 24, 2025
  • #21
R82148V said:
Hey everyone,

I have a strange idle issue. when the engine is warmed up it idles good but as soon as you tap the gas or stop at a red light, idle goes up to about 1200 and slowing comes back down under 1000. It’ll usually hunt a little then finally calm down. Did a smoke test and found three areas of a lot of smoke leaking. Egr valve out the vent holes, out the tps and i even have a tps without a hole and the last leak is under the TB at the spring shaft. all three locations was releasing a ton of smoke. TB is stock from 1987. Is this TB toast? would I be able to rebuild the seals or better to just upgrade? I read that they all leak a little but there was a ton of smoke coming out .
Click to expand...
Time to replace the throttle body, EGR, and TPS. Now might be a good time to remove EGR and put an EGR delete plate on it.
 
J

Jarhead67

5 Year Member
Nov 24, 2018
171
64
38
Windsor Locks, Connecticut
May 24, 2025
#22
  • May 24, 2025
  • #22
R82148V said:
Hey everyone,

I have a strange idle issue. when the engine is warmed up it idles good but as soon as you tap the gas or stop at a red light, idle goes up to about 1200 and slowing comes back down under 1000. It’ll usually hunt a little then finally calm down. Did a smoke test and found three areas of a lot of smoke leaking. Egr valve out the vent holes, out the tps and i even have a tps without a hole and the last leak is under the TB at the spring shaft. all three locations was releasing a ton of smoke. TB is stock from 1987. Is this TB toast? would I be able to rebuild the seals or better to just upgrade? I read that they all leak a little but there was a ton of smoke coming out .
Click to expand...
LMR has Accufab, BBK, and SVE throttle bodies. SVE are a little cheaper.
Have you checked CJPony or BLUEOVAL?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,076
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Box behind Walmart
May 24, 2025
#23
  • May 24, 2025
  • #23
Jarhead67 said:
LMR has Accufab, BBK, and SVE throttle bodies. SVE are a little cheaper.
Have you checked CJPony or BLUEOVAL?
Click to expand...

Did you read the whole thread?

Fixes are already in motion.
 

R82148V

Active Member
May 26, 2020
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May 30, 2025
#24
  • May 30, 2025
  • #24
Update -

Just received the Accufab 65mm TB and matching EGR. Working on port matching the intake to match the EGR spacer and installing all the other parts to it. This thing is beautiful! Updates to follow
 
Reactions: Noobz347 and gkomo

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,076
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234
Box behind Walmart
May 30, 2025
#25
  • May 30, 2025
  • #25
R82148V said:
Update -

Just received the Accufab 65mm TB and matching EGR. Working on port matching the intake to match the EGR spacer and installing all the other parts to it. This thing is beautiful! Updates to follow
Click to expand...

I've suggested to Accufab before that they need to make throttle body Christmas tree ornaments.
 
Reactions: R82148V

R82148V

Active Member
May 26, 2020
256
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38
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Jun 4, 2025
#26
  • Jun 4, 2025
  • #26
R82148V said:
Update -

Just received the Accufab 65mm TB and matching EGR. Working on port matching the intake to match the EGR spacer and installing all the other parts to it. This thing is beautiful! Updates to follow
Click to expand...

Update -

LOOKS AND FEEL
TB and EGR spacer has been installed. Looks great! I noticed the throttle blade doesn't have that small hole the way the stock one does.
It runs so so much better, cleaner and much more throttle responsive. Also, with the stock TB at highway speeds, 4th gear going into higher RPMS, you could feel almost like a drop off in pull once you reached 4000ish. Like it was running out of breath or something. With this 65mm Accufab, that feeling is gone! At 4k rpm in 4th, it just wanted to keep pulling !!

IDLE
I did the idle reset but only how accufab instructed me to. To get the TPS at .98 v and never touch the throttle plate screw. I did this on a cold engine though.
Idle seems better than it was with the RPMS dropping quickly to idle. Hunting is almost gone but still a little there.? No where as bad as before.
Could this be because I did the base idle adj at cold or is the PCM still learning?
I never did the full base idle adjustment that we all know about as in un plug the spout, and IAC, do adj with engine off then disconnect the batt and run it for 2 min with no accessories on then 2 mins with on? would this sort of this be best?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Jun 4, 2025
#27
  • Jun 4, 2025
  • #27
Try the computer reset,
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
43,076
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234
Box behind Walmart
Jun 4, 2025
#28
  • Jun 4, 2025
  • #28
You cannot properly set idle with the spout connector in. The EEC tries to makeup for your screw adjustments with timing.
 
Reactions: General karthief

R82148V

Active Member
May 26, 2020
256
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Jun 5, 2025
#29
  • Jun 5, 2025
  • #29
Noobz347 said:
You cannot properly set idle with the spout connector in. The EEC tries to makeup for your screw adjustments with timing.
Click to expand...
I'll do the base idle reset again but the full version with the spout conn out. I'll report back !!

Thank you!
 
Reactions: General karthief and Mcmahst
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