Several (see: 5) days ago, I pulled out of my driveway, and onto the main road I live by. I give her some gas like normal, but it feels odd just sort of sluggish. RIGHT AT 3,800rpm (Always occurs at 3.8k) boost just feels like it hits, a sudden momentary surge, then the check engine light comes on. Sometimes it goes off immediately, sometimes it waits til I'm a minute down the road. It's done this steadily since then, but only that initial first little bit of boost.

 

Today however, was a different story. It happened when I left the house, then once coming home from work. In the time the code stays on, I don't think I can (quickly enough) get the ecu to flash codes at me, so I'm sort of at a loss.

 

ANY help would be appreciated. Oil levels are good, as are coolant levels. I haven't checked to make sure the turbo is still in good condition, but I plan to this weekend. The vehicle only smokes from under the hood (Still need to service that oil pump gasket) but nothing from the exhaust. Boost is set at 10psi, and the vehicle has an Intake and an uncapped (see: bolts backed their way out of the exhaust pipe -> muffler flange) exhaust. Other than that, no mods have been done, but I'm not the completely knowledgable as to what the previous owners may have done.

 

Thanks for any suggestions you may have.

maybe the throttle position sensor. is it turbo? sometimes mine will dook out just to hit all at once when i hit the gas. was a bad TPS

if you are getting a CEL, there is a code. Check the stored codes before you go ripping the turbo off... as a matter of fact, don't rip the turbo off.. its not worth the effort as the chances of it being your problem are about .0001%

 

Fox's ideal of a sticky TPS is more likely

I was going to check to make sure there wasn't any shaft play and such in the turbo, not pull the whole thing.

 

I didn't know if the computer was like the TCCS (Toyota Computer Control System) or not, the TCCS doesn't store codes like that. I'll be sure to check them tonight.

 

How can I check to see if the TPS is at fault?

the mounting holes for the TPS are slotted, you can loosen the screws and move the tps one way or the other. on ours it semed to help. sometimes it will dook out, but not as bad. its not hard to replace, but you may want to take off the alternator an get a short screwdriver to access it.

 

the turbo itself has no electricals or whatever, it's driven by exhaust pressure, the turbo would not send a code to the ECU

 

you can search for code reading, its posted all over the place, somewhere there is a chart that explains the codes.

I'm quite familiar with turbocharging, I understand however it's something I hadn't checked on the vehicle yet. I've seen much weirder things happen (boost spiking, overboost conditions, etc.) Besides that fact it seems odd to have boost coming on as late as it does (3.5-4) with such a tiny turbo. So it's something I plan to check.

 

Is there not an official TPS calibration procedure?

the haynes manual will have a procedure for checking the tps, such as a closed throttle voltage, a WOT voltage, and resistences between. not so much a calibration but a check to see if its within spec

Alright, I was just curious. I know that in my supra I have to use a feeler gauge and a multi-meter. Was just curious if there was such a thing on the ea82t.

yes there is but i don't have my book in front of me right now