PTE TA49 Turbo + Terry Houston 3.5 Down Pipe DP + 3" Chrome Maf Pipe

grass doctor

Dream Catcher
yes it is normal...what are your goals with the car ...couple of monthly drives ...and preserve its value ...or run it weekly ??...sounds like you just need to due all general maintenance ...bc of age ...and freshen everything up ...its such a low mile car but still 33 years old ...pics of the car would be great ...we love pics ... :love: ....
 

GNX-481

New Member
yes it is normal...what are your goals with the car ...couple of monthly drives ...and preserve its value ...or run it weekly ??...sounds like you just need to due all general maintenance ...bc of age ...and freshen everything up ...its such a low mile car but still 33 years old ...pics of the car would be great ...we love pics ... :love: ....
Yeah totally a weekend type of thing once in a while.
I'm taking some pics now
 

samgauto

Member
Just got the Actron CP9690. Only item it doesn't display is Mass airflow. But very helpful otherwise. I think my old snap on scanner showed MAF in grams per second on these cars. I reset my TPS from .39 to .43 and my WOT value is 4.24 from drivers seat and accelerator pedal can't travel any further as the driver's side throttle bracket that cables are connected too is at the limit and up against stop on throttle body near idle screw. You can actually push the TPS lever itself on passenger side of throttle body a little further to get tps to 4.90 max but obviously that's not opening the throttle blade any more. Tps power and ground are good. Perhaps this is normal.
 

GNX-481

New Member
@samgauto - yeah I noticed that was missing.

@grass doctor - can't seem to get idle below 1000 - 950, even at 191 COOLANT
do you know if the IAC is correct ? I out a frame from 35
Seems there is no way this car can idle below 750, would stall in my case. It tries to drop down on initial start and returns to high idle when it realizes its going to stall, it will stay in that high zone.

Frame 0 (time 0.0):
BLM-1340
Coolant -183
EGR % -0
RPM -950
ESC Counter- 8
Exhaust 02 - LEAN
IAC position - 69
LOOP status - closed
02S(mV)-160
02S CroosCnts-174
spark adv (degrees)-41
TPS-.43


Here is me giving it a little throttle :

Frame 35 (time 95.0):
Coolant -192
EGR % -0
RPM -1025
ESC Counter- 2
Exhaust 02 -RICH
IAC position - 62
LOOP status - closed
02S(mV)-733
02S CroosCnts-156
spark adv (degrees)-42
TPS-.43
 

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Anthony P

sharing knowledge with those who care to listen
Gents, glad you've rec'd your scan tools. not sure why MAF value is not in parameters...but I could be thinking back to the AutoXray 5000/6000 as that is what I used when I created that parameter spreadsheet and not the current Bosch-Actron tool.

Idle air motor position at 69 steps or 62 steps is high. that is why the engine idle RPM is at 950/1025.

need to adjust throttle plate stop screw to change Idle Air Control valve steps value. driver's side of throttle body, the adjustment screw is under that silver vinyl cap. suggest using the soft heat from a hair dryer to soften cap first so as to permit easier removal of the silver cap without leaving marks from hose picks or small screwdrivers.

turning that screw CW will lower the IAC steps counts. Adjustments must be done with engine at normal operating temp. Seeing your pics above, I'd conclude the factory 180F T-stat is in place. so adjustments in closed loop about 180F or higher.

with engine up to temp, turn screw CW a quarter turn to start. monitor IAC step value. keep making minute adjsutments to get it down to 30.

shut off engine - IAC motor resets position when engine is shut off. with engine off, now have to re-check TPS value. so switch ignition to key ON, check and probably adjust TPS to get back to 0.42 to 0.44. Once TPS is set, go ahead and re-start engine.

Once in CLOSED loop and up to temp, check IAC step value again. Probably have to adjust again - CW to lower IAC steps, CCW to increase.

You'll have to do this IAC and TPS back and forth a few times - eventually achieving IAC steps value of 10 to 30 with TPS value of 0.42 to 0.44 V.

In OPEN loop, the ECM is using pre-defined data tables for fuel mixture. Once in CLOSED loop, the ECM will use the O2 sensor data for fuel trim. that's a very simplified explanation...RICH/LEAN flag is two-position - adding fuel or removing fuel as needed to maintain air/fuel ratio.

RICH/LEAN, Fuel trim, Block Learn and Integrator values are well reviewed in a video link that @Jerryl posted a few years back. get a comfy seat and some snacks as the presentation is about 50 minutes...
LINK => What are BLM & INT?

side note: I had to look up in my build data records about #481. I first thought that # sounded familiar as the Miller Brewing Company Employee Investment Pool vehicle stored at Miller. when the employees cashed in their investment in 2009, it had 9.7 miles so I thought it was taken for a few trips around the block to get to 467 recorded miles. but the Miller car is # 482.
 
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GNX-481

New Member
Gents, glad you've rec'd your scan tools. not sure why MAF value is not in parameters...but I could be thinking back to the AutoXray 5000/6000 as that is what I used when I created that parameter spreadsheet and not the current Bosch-Actron tool.

Idle air motor position at 69 steps or 62 steps is high. that is why the engine idle RPM is at 950/1025.

need to adjust throttle plate stop screw to change Idle Air Control valve steps value. driver's side of throttle body, the adjustment screw is under that silver vinyl cap. suggest using the soft heat from a hair dryer to soften cap first so as to permit easier removal of the silver cap without leaving marks from hose picks or small screwdrivers.

turning that screw CW will lower the IAC steps counts. Adjustments must be done with engine at normal operating temp. Seeing your pics above, I'd conclude the factory 180F T-stat is in place. so adjustments in closed loop about 180F or higher.

with engine up to temp, turn screw CW a quarter turn to start. monitor IAC step value. keep making minute adjsutments to get it down to 30.

shut off engine - IAC motor resets position when engine is shut off. with engine off, now have to re-check TPS value. so switch ignition to key ON, check and probably adjust TPS to get back to 0.42 to 0.44. Once TPS is set, go ahead and re-start engine.

Once in CLOSED loop and up to temp, check IAC step value again. Probably have to adjust again - CW to lower IAC steps, CCW to increase.

You'll have to do this IAC and TPS back and forth a few times - eventually achieving IAC steps value of 10 to 30 with TPS value of 0.42 to 0.44 V.

In OPEN loop, the ECM is using pre-defined data tables for fuel mixture. Once in CLOSED loop, the ECM will use the O2 sensor data for fuel trim. that's a very simplified explanation...RICH/LEAN flag is two-position - adding fuel or removing fuel as needed to maintain air/fuel ratio.

RICH/LEAN, Fuel trim, Block Learn and Integrator values are well reviewed in a video link that @Jerryl posted a few years back. get a comfy seat and some snacks as the presentation is about 50 minutes...
LINK => What are BLM & INT?

side note: I had to look up in my build data records about #481. I first thought that # sounded familiar as the Miller Brewing Company Employee Investment Pool vehicle stored at Miller. when the employees cashed in their investment in 2009, it had 9.7 miles so I thought it was taken for a few trips around the block to get to 467 recorded miles. but the Miller car is # 482.
Anthony, I got her down to 29 IAC, .43 tps, @198 temp. Still idleing around 1000 rpm anyway to get that down to normal?
 

Anthony P

sharing knowledge with those who care to listen
Hi Tom, wonderful...those are the #'s for IAC, TPS and coolant temp I'd expect to see on an original car with factory PROM chip, both GNX and regular turbo regal.

I'm suspecting the IAC motor plug, spring and passages in the throttle body are gummed up with oil residue possibly affecting minimum air thus RPM. and as someone noted, the throttle plate is most like black with oil residue as is the indside of the up-pipe. and the intercooler need attention as well.

the factory breather system on the pass. valve cover permits the turbocharger to suck atomized oil, even more when under boost conditions. there is probably about an ounce of liquid engine oil sitting at the bottom of the intercooler. to solve that issue, folks install a stand alone breather in the pass. valve cover and cap the port on the inlet bell of the turbo. Kirban's sells that kit, part # 1580 seen here =>

1986 1987 Buick Regal Grand National Turbo T T-Type GNX Passengers Side BREATHER BY-PASS KIT #1580

it's a simple S & B breather with an aluminum base - 1" diameter. something to consider to stop the sucking and coating of oil on the intake components.

intercooler is removed and cleaned as well as cleaning of IAC motor, passages and throttle plate. do it once and it's done. re-connect the factory breather system and back in the same mess over time.

for now let's focus on just the IAC motor and passages. up pipe will have to be removed - take care with that pipe as it's a ceramic coating. please use a 5/16" nut driver on the intercooler hose clamps. a standard tip screwdriver blade is too narrow for the slot in the clamp's screw and mars the slot. the original clamps are Tridon brand, stainless steel (conversion coated black oxide), made in Canada. replacement stainless Tridon clamps found today are made in USA. inlet air charge temp post intercooler is ~ 300F under boost so the oil laden inlet air coats every thing and get a baked-on stickiness to it. remove MAF hose as well to permit easy disconnect of 4-wire plug from IAC motor. use a throttle body cleaner and rags to clean throttle plate and air passages for.

you have your pics of the engine bay. for re-assembly line up the hoses and hose clamps where they were. don't over torque the hose clamps. most would not care where stuff or how stuff get re-installed, but this is not a driver. not hard to align the hose clamp impressions during reassembly.

try cleaning the IAC motor spring/pintle and the passages in the throttle body and throttle plate itself for now.
 

Anthony P

sharing knowledge with those who care to listen
@samgauto,

your TPS setting results are not uncommon. could try this if so chosen. loosen TPS screws. move TPS as far forward as both upper and lower slots permit. barely tighten screws to hold TPS position but still permit adjustment movement. keep bottom slot all the way forward, using as a pivot for the upper slot to move backwards to set the minimum value. hopefully I described that correctly.

some will note that the oval slots can be cleaned up and lengthened or expanded with use of a round file. however, that really is not necessary as the factory PROM chips as well as Eric's TT chips enter power enrichment mode when TPS voltage is above 4.0.

floor mat was removed when checking WOT TPS value sitting in the driver's seat, yes? if correct, and 4.30V is your max, that is fine. the stroke from idle to WOT is only so much, less than what the TPS cam lever is capable of being rotated. the lower the TPS minimum value is set, the lower the WOT max will be. Service manual notes TPS value above 0.48, the ECM thinks the car is driving and not at idle. some write-ups note TPS min setting of 0.40 to 0.46 but tightening up that range to 0.42 - 0.44 is a bit better considering how the setting can change ever so slightly accounting for a possible 100F temperature change in ambient air - winter or summer conditions.
 
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Haulz A

Active Member
Anthony, I got her down to 29 IAC, .43 tps, @198 temp. Still idleing around 1000 rpm anyway to get that down to normal?
You gotta vacuum leak somewhere on the car- if those are original vacuum lines- they are probably a few lines that are dry rooted due to age. The car is 33 years old and needs some TLC. Anthony is definitely right about the old fuel in the tank which is always a problem with a long time stored car. The BLM's is adding fuel and the idle is high even tho you have adjusted the IAC and TPS sensors to spec.
 

GNX-481

New Member
Hi Tom, wonderful...those are the #'s for IAC, TPS and coolant temp I'd expect to see on an original car with factory PROM chip, both GNX and regular turbo regal.

I'm suspecting the IAC motor plug, spring and passages in the throttle body are gummed up with oil residue possibly affecting minimum air thus RPM. and as someone noted, the throttle plate is most like black with oil residue as is the indside of the up-pipe. and the intercooler need attention as well.

the factory breather system on the pass. valve cover permits the turbocharger to suck atomized oil, even more when under boost conditions. there is probably about an ounce of liquid engine oil sitting at the bottom of the intercooler. to solve that issue, folks install a stand alone breather in the pass. valve cover and cap the port on the inlet bell of the turbo. Kirban's sells that kit, part # 1580 seen here =>

1986 1987 Buick Regal Grand National Turbo T T-Type GNX Passengers Side BREATHER BY-PASS KIT #1580

it's a simple S & B breather with an aluminum base - 1" diameter. something to consider to stop the sucking and coating of oil on the intake components.

intercooler is removed and cleaned as well as cleaning of IAC motor, passages and throttle plate. do it once and it's done. re-connect the factory breather system and back in the same mess over time.

for now let's focus on just the IAC motor and passages. up pipe will have to be removed - take care with that pipe as it's a ceramic coating. please use a 5/16" nut driver on the intercooler hose clamps. a standard tip screwdriver blade is too narrow for the slot in the clamp's screw and mars the slot. the original clamps are Tridon brand, stainless steel (conversion coated black oxide), made in Canada. replacement stainless Tridon clamps found today are made in USA. inlet air charge temp post intercooler is ~ 300F under boost so the oil laden inlet air coats every thing and get a baked-on stickiness to it. remove MAF hose as well to permit easy disconnect of 4-wire plug from IAC motor. use a throttle body cleaner and rags to clean throttle plate and air passages for.

you have your pics of the engine bay. for re-assembly line up the hoses and hose clamps where they were. don't over torque the hose clamps. most would not care where stuff or how stuff get re-installed, but this is not a driver. not hard to align the hose clamp impressions during reassembly.

try cleaning the IAC motor spring/pintle and the passages in the throttle body and throttle plate itself for now.

Here is the throttle body photos, very clean.

you can see the previous owner got a little over-zealous on lubing the TPS :).
 

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Anthony P

sharing knowledge with those who care to listen
Gee, well that is super clean Tom so scratch exploring oil residue buildup on the IAC motor pintle and passages.

Like @Haulz A noted, time to explore a vacuum leak. going to need a hand vacuum pump.

with 467 miles on a car basically still in the wrapper, I'll discount worn shaft seals on the throttle plate shaft. let's leave the vacuum block attached to the throttle body and focus on the soft lines at the end of the 5 hard lines.

one line is to the PCV valve. it's heavy walled hose and probably fine. blocking the PCV line will reduce vacuum pulled thru pcv valve but will most likely mask a small vac leak elsewhere - the real cause of the problem.

the other line right there is the take-off for the in-dash boost gauge. how is the rubber transition from the hard metal line to the nylon line? and the nylon line for what you can see.

one line goes to fuel pressure regulator - how's the rubber adapter, 90* hard line and rubber cap to fpr?

in the same area is the take-off for the long rubber hose to the charcoal cannister/fuel vapor solenoid. this is the only line I've had to replace on my GN. the rubber was deteriorating and would turn your hand black where you touched it. also, just wiping it with a water wetted rag would turn the rag black.

another take-off there from the 3rd hard line goes to the EGR valve; EGR solenoid and back to the firewall to more connections. at the firewall, one long hose comes around the inner fender to catch cruise control and has a "Y" branch to the vacuum ball. a hard nylon line goes alone the firewall and A/C box and is wrapped together with the hard nylon line to the heater valve.

suggest pulling vacuum directly on EGR valve as some have experienced a failed diaphragm.

how are the connections at the vacuum ball? can test that whole length by pulling vacuum on the line back at the firewall where it tee's off with the hard nylon line to HVAC control. just wondering if a rodent has nibbled on something...

others have noted a vac leak at the A/C switch at the head unit HVAC control in the car. that can all be isolated in stages, checking sections from the tee at the firewall and at the vac ball.

it's a start....somebody can check my thought process.

hey @X Ray, where are you Rick? thought you'd be all over this one in the wrapper?
 

Anthony P

sharing knowledge with those who care to listen
Hi Rick, I discounted the possibility of a shaft seal issue since this is a 400 documented mile example - little use.

I believe the shaft seals are nitrile rubber. As a synthetic rubber, its inherent properties as a seal, in a compressive state, not exposed to sunlight would only break down as a function of wear over time as a result of repeated, actuated, focused contact use greater than the compound's abrasion and tear resistance.

while the seals are 33 years old, they've seen little focused rotational contact. with this car being in a static environment, time alone is not the issue. it's more of a function of wear thru use over time, as I see it. with minimal use, can't expect a wear issue.

Timco's nitrile rubber properties page below goes into greater material specificity.

Nitrile Rubber, NBR, Buna-N Rubber
 

samgauto

Member
I did notice something interesting today. With the
Some of those scantools force ALDL mode. ALDL mode forces commanded idle to 1000rpm.

If a vacuum leak caused a high idle, IAC would likely be 00.
This is correct. I noticed with scan tool connected today that my idle is higher and around 1000rpm. Drops to about 850 when tool is disconnected from aldl.
 

Anthony P

sharing knowledge with those who care to listen
Some of those scantools force ALDL mode. ALDL mode forces commanded idle to 1000rpm.

thank-you so much Eric for chiming in. I did not realize that and really haven't noticed that. My old AutoXray scan tools are just for turbo Regal work (and don't do what you noted) whereas the updated Bosch-Actron tool is used on my newer cars as needed - color display graphing, printing reports, etc when needed.

your input stopped a wild goose chase. thanks for taking a moment to chime in.
 

GNX-481

New Member
@Anthony P ,@X Ray I used the Actron to set both the IAC and tps. After disconnecting the Actron the idle is much better! Idles warm around 750. I am in San Diego does anyone know someone reputable I could trust to give it a once over ?

-tom
 
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