Supercharger wizard needed (1 Viewer)

[santacruzpaul]

Five years ago I found a NOS TRD supercharger at an East Coast Toyota dealership and had my local dealership install it on my 1997 80 series. For the first 3 years I battled low octane California “premium“ fuel engine knock at low rpm high gear loading. After replacing stock plug wires and installing iridium racing plugs, the knock improved. That was going great for a year but now it’s been a year of chasing an intermittent, unpredictable low idle (200 rpm) that I cannot reproduce for the mechanic. Three times however the condition has thrown a 0401 code (insufficient egr flow) and the modulator, vsv valve have been replaced. The error code resets but has returned. We’ve replaced the air/idle control valve and traced all emissions and vacuum lines verifying against the factory and Magnuson diagrams. The MAF and throttle body have been cleaned and fuel pressure has been verified. Vacuum readings are within normal. Fuel economy is normal and performance is great when driving but coming up to a stop, I just don’t know if it’s going to sputter or flat out stall. If I have to hit the starter, 9 times out of 10 it returns to a solid 650 rpm idle. I’m fully expecting another code any day now so any feedback would be appreciated.

 

[landtank]

check your throttle cable, if i looks ugly change it. What can happen is the cable hangs up which elevates the RPMs. The IAC compensated for that and drops the idle. The next time the cable doesn't hang up and the IAC is set low so the engine barely runs or stalls. Because of the routing of the cable on SC trucks this is more prevalent.

 

[Francis K]

I had a similar issue but it wasn't caused by a supercharger so maybe it doesn't apply but blocking off the Egr fixed it for me....

 

[landtank]

I had a similar issue but it wasn't caused by a supercharger so maybe it doesn't apply but blocking off the Egr fixed it for me....

My daughter had a Camry that would die at the first stop light after driving on the highway like clockwork. Turned out to be a sticky EGR valve.

 

[ajax1]

Stuck egr will cause this and since your code is for egr………..

 

[Saito]

Go two heat ranges colder on the plugs as well, if you haven’t already . . .cuz pre-ignition was an issue w/ my SC and normal plugs in the summer.

 

[santacruzpaul]

I surely appreciate all the replies and advice. The supercharger makes it a challenge for the average Toyota mechanic who has no experience even working on a 25 year old Land Cruiser. I traced all of the throttle cable and lubed the pedal and all exposed cable and connectors. I pulled the EGR valve and there was pretty good carbon build up. Even though the valve seemed to operate without sticking, I replaced it and a new gasket after a thorough wire brush and carb cleaner spray of the pipe and intake. Reset Check Engine Light and it started up perfectly. The real test will be next 100 miles without a stall.

 

[santacruzpaul]

I surely appreciate all the replies and advice. The supercharger makes it a challenge for the average Toyota mechanic who has no experience even working on a 25 year old Land Cruiser. I traced all of the throttle cable and lubed the pedal and all exposed cable and connectors. I pulled the EGR valve and there was pretty good carbon build up. Even though the valve seemed to operate without sticking, I replaced it and a new gasket after a thorough wire brush and carb cleaner spray of the pipe and intake. Reset Check Engine Light and it started up perfectly. The real test will be next 100 miles without a stall.

Update. Any more ideas? Please! 100+ miles more on the clock with the new EGR valve but the intermittent, low idle/stall condition persists. It hasn't thrown a code or check engine light yet but I figure it's just a matter of time. At speed, it runs great, performs super under heavy throttle pressure, cruises smoothly without surge and mpg is 12-15. A trip back to my local import mechanic has again left us scratching each others' heads. The TRD blower disengages at lower rpm so that's not dragging and the 200 rpm near stall does slowly build back to 650 rpm after about 4-5 minutes at idle. Now he's talking like it must be the computer. I really hate to hear that. His other "suggestion" is a trip to the dealer where they see a 26 year old Land Cruiser like never. Having replaced what appears to be the entire egr circuit, verified all vacuum and emission hose routing, I'd greatly appreciate any input.

 

[zpilot]

Maybe smoke test for vacuum leak?

 

[lumbee1]

Have you replaced the throttle cable?
Have you inspected the EGR valve after install?
Have you considered removing EGR completely or can you do that living in CA?

 

[landtank]

anything funky with the air intake like a cone filter or other non toyota things?

 

[santacruzpaul]

Have you replaced the throttle cable?
Have you inspected the EGR valve after install?
Have you considered removing EGR completely or can you do that living in CA?

While I didn’t replace the throttle cable, it was inspected for any wear or fraying and got dry lubed from the pedal to the linkage.

The new EGR valve is operating normally and not sticking so what is it that I would be inspecting?

EGR removal is a big fine in California if you get pulled over.

 

[santacruzpaul]

anything funky with the air intake like a cone filter or other non toyota things?

Nope. All stock intake. The intermittent condition feels like sensor or calibration that is only affected at normal operating temperatures. Cold start gives 1200 rpm idle decreasing to 650 while warming up. 30 minutes stop and go driving more predictably causes low idle, but not always. Frustrating.

 

[landtank]

if this has been mentioned I appologize, but have you cleaned your MAF? Low air flow conditions can be a challenge for a dirty MAF. Also with the way the harness hangs off the sensor the female pins can get fatigued and need to be bent to make better contact.

 

[lumbee1]

While I didn’t replace the throttle cable, it was inspected for any wear or fraying and got dry lubed from the pedal to the linkage.

The new EGR valve is operating normally and not sticking so what is it that I would be inspecting?

EGR removal is a big fine in California if you get pulled over.

You could install block off plates behind the EGR pipe to test this. I'm in North Carolina and completely removed my EGR system and made my own block off plates out of steel.

 

[santacruzpaul]

Update to the ongoing saga. This is a real head scratcher. Wherever I go, mechanics draw back in fright seeing the TRD supercharger and jump to the assumption that the performance issue is related to the supercharger. Here's a new thought after all the focus on the egr system replacements. I finally checked the alternator charging system and found that I've been limping along on a bad battery. The great tuning has required only a small bump on the starter to fire up and I never realized the battery was barely 11 volts. Quick trip to Costco for a replacement and fired up in the parking lot. Wow! The idle jumped to 1400 rpm even though the engine was still warm but not hot. A 10 minute idle brought it to 800 rpm but still a bit high but no stall or stutter all the way home. I'm hoping the ECM will catch up and bring things along. Question for any followers. As I was coming to a hot engine idle and the rpms dropped, the charging system would go to battery power for ignition but the old battery was barely 11 volts. Hot battery, even lower voltage, less ignition. Voila! 200 rpm. More throttle, alternator kicks in and perfect performance. Don't fear the supercharger. Look for basic air/fuel/ignition. I'll put more miles on over the next week and update but sure appreciate all advice.

 

[lumbee1]

Update to the ongoing saga. This is a real head scratcher. Wherever I go, mechanics draw back in fright seeing the TRD supercharger and jump to the assumption that the performance issue is related to the supercharger. Here's a new thought after all the focus on the egr system replacements. I finally checked the alternator charging system and found that I've been limping along on a bad battery. The great tuning has required only a small bump on the starter to fire up and I never realized the battery was barely 11 volts. Quick trip to Costco for a replacement and fired up in the parking lot. Wow! The idle jumped to 1400 rpm even though the engine was still warm but not hot. A 10 minute idle brought it to 800 rpm but still a bit high but no stall or stutter all the way home. I'm hoping the ECM will catch up and bring things along. Question for any followers. As I was coming to a hot engine idle and the rpms dropped, the charging system would go to battery power for ignition but the old battery was barely 11 volts. Hot battery, even lower voltage, less ignition. Voila! 200 rpm. More throttle, alternator kicks in and perfect performance. Don't fear the supercharger. Look for basic air/fuel/ignition. I'll put more miles on over the next week and update but sure appreciate all advice.

After installing my supercharger and replacing my main engine harness, my first fire up was quite eventful. It took 2 to 3 cranks to get it started. When it did start, it was idling at 300 to 400 rpm and barely running. I shut it off and double checked everything I touched during the install. I was sure I forgot something however I couldn't find anything wrong. I started the engine again and this time it surged to 1200 or so but settled to around 500 rpm. I let it idle for a bit but never gave it any throttle. Eventually the computer started learning and rpms climbed to 650 and stabilized.

 

[inkpot]

Update. Any more ideas? Please! 100+ miles more on the clock with the new EGR valve but the intermittent, low idle/stall condition persists. It hasn't thrown a code or check engine light yet but I figure it's just a matter of time. At speed, it runs great, performs super under heavy throttle pressure, cruises smoothly without surge and mpg is 12-15. A trip back to my local import mechanic has again left us scratching each others' heads. The TRD blower disengages at lower rpm so that's not dragging and the 200 rpm near stall does slowly build back to 650 rpm after about 4-5 minutes at idle. Now he's talking like it must be the computer. I really hate to hear that. His other "suggestion" is a trip to the dealer where they see a 26 year old Land Cruiser like never. Having replaced what appears to be the entire egr circuit, verified all vacuum and emission hose routing, I'd greatly appreciate any input.

Curious how the supercharger DISENGAGE at low rpm? Mine does not. Mine does have a vacuum operated bypass valve built into the kit.

 

[santacruzpaul]

Curious how the supercharger DISENGAGE at low rpm? Mine does not. Mine does have a vacuum operated bypass valve built into the kit.

I can’t say with confidence where I read, or heard that. I think it’s a function of throttle pressure/vacuum rather than pure rpm. I either read or was told that Magneson was touting their longevity design that didn’t “run” the blower all the time.

 

[scottryana]

I can’t say with confidence where I read, or heard that. I think it’s a function of throttle pressure/vacuum rather than pure rpm. I either read or was told that Magneson was touting their longevity design that didn’t “run” the blower all the time.

Blower spins all the time.