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Discussion Starter · #1 ·
My car's learned a new trick - at idle, I'm seeing BLMs go from around 120 to around 135. It happens like this: it'll stay at 128 for about 20 seconds, then jump to 120 for a few, then back to 128 for while, then to 135 briefly, then back to 128 for a while. All the while, idle speed is hunting. Previously, I had BLMs fairly steady between 128-130, and it would never just jump 10 counts and then back.

Along with this, there is a miss at ~1200 RPM, whether stopped or rolling, hot or cold. From a stop, it's felt as a tip-in stumble. At speed, holding that RPM, it just feels like you pulled a wire. All other RPM ranges seem fine - no missing.

This problem has remained through 2 sets of injectors, 2 different coil pack/modules, a few sets of plugs...any ideas?

Car is mostly stock, with Lubrant street chip and a new O2 with good cross counts. I'm stumped. Any ideas appreciated.

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Had to leave Hawaii for Oregon, but at least now I have...
"Toady" -- white/blue '86 T-Type, 175k+
Probably the only TR in the NW that still has stock turbo/IC/injectors/DP
 

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Discussion Starter · #3 ·
Thanks, Steve, will do. Do you suppose it could be an exhaust leak or the cam sensor/timing chain going out?
 

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It's not the changing BLM's that are the problem. It's the hunting idle that is causing the PCM to see 3 different BLM cells (there are a total of 16 cells).

Need to get that hunting idle cured.
How's the IAC and TPS adjustments????
Vacuum leaks??



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TurboDave & Kathy Huinker, mailto:[email protected][email protected]</A>
TurboD Racing
Lone Rock, WI
86 GN[email protected](MM/MAF Xlator/Extender,MM BstC Boost Command,THDP,PTE44,CAS V2FM,MSD50's,9.5"vigilante 3500)
87 GN [email protected](Stock)
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01 Excursion LTD TTS"race" chip 7.3L PSD(power stroke diesel) Turbo 4X2
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Originally posted by TurboDave:
It's not the changing BLM's that are the problem. It's the hunting idle that is causing the PCM to see 3 different BLM cells (there are a total of 16 cells).

Need to get that hunting idle cured.
How's the IAC and TPS adjustments????
Vacuum leaks??

YES! Glad to have you back Dave!! If your idle is 789-800RPM you are bouncing from cell 0 to cell 1. You say 3 values, well, if the idle goes to 1100 RPM theres the 3rd cell.

Are you sure you arent watching INT?



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Jim Testa
1986 Regal T-Type
Stock block w/girdle, stock rods, TRW's, JE pins, 214/210 roller, TurboMotion port/polished heads w/1.77-1.50 valves, T&D roller rockers, Champ intake w/o EGR, PTE plenum, Accufab 70mm TB, MSD50's, TE61, PTE front mount, SMC alcohol inj, JT trans, 3000 vigilante, stock rear w/Hotchkiss arms, and kick ass tunes..

 

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Discussion Starter · #7 ·
Jim, Dave - thanks for your insights. It never even occurred to me that it was skipping BLM cells. Jim, I am sure it is BLM and not integrator numbers I'm watching.

I did a spray with carb clean to check for vac leaks, but found none so far. What I did find was a bunch of oil in the TB and up-pipe.
I'm thinking that maybe my original stock turbo's seals are leaking and that the IAC is gunked up. I haven't had time to pull that yet, between working 3 weeks straight and having a 9-month-old daughter... Fortunately, I don't have to drive it every day now, so some of this stuff is just quirky instead of *%&#^ maddening.
 
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