Wird idle and chek engine light

[cre]

I accept all major credit cards.

Seriously though... Check your ignition timing, once you're sure that's set properly insert the diagnostic mode jumper firmly and go for a drive with a passenger. Have them count the flashes and jot down which codes come up. The only code which should appear is 51, that's normal. I hate to say it but if not a boost leak or AFM with damage that the ECU isn't catching it sounds a lot like knock. The Check Engine light is the only one that comes on when it stumbles? No battery or any others? That would be indicitive of a power issue. Do you have to turn off the car to get it running right again? Have you inspected the ignition components? Plugs, wires, coils, igniter?

This "it would be hesitant kinda like a boost leak then id get to speed and it will be normal" sounds exactly like a boost leak. The fact that it is intermittent is not common but does happen. A tight boost leak will only leak after a certain level of pressure is met; The "cracking pressure"... The pressure at which the leak will stop passing air again is always lower than the cracking pressure. So if you've got a leak which doesn't open until 12psi, your boost spikes to 12psi before leveling at 11psi and the leak seals at 10psi you will experience the following:

1) You accelerate and build boost normally.
2) The car stumbles when the leak opens at 12psi.
3) The wastegate stabilizes pressure at 11psi but the engine is working too hard and the ECU sees too much air coming through as the leak is still dumping air.
4) You let up and pressure drops below 10psi, the leak closes, the ECU sees that the measured airflow is back within spec and the CEL turns off.
5) You accelerate more but with caution and as the wastegate is already open there is no spike to force the leak open.... You assume all is well. You're still actually going to be leaking some air but it's a relatively benign amount.

The only problem is that this should set a code for either the AFM or turbocharger pressure. Search via Google for "DIY boost leak detector" for an inexpensive way to pressure test the system, don't exceed 15 or 16psi.

Anyway, if the CEL comes on a code will be stored 90% of the time. Only real time, non-critical codes are not stored once the detected problem is no longer evident. I'm not sure if some trouble events require a certain time period before they are set... If there are any then you may need to drive for a while before you see a code stored for that particular event.


I'm quite tired and out of it... I believe all of this is relevant to the MKIII but you might want to check back for edits tomorrow.

[forgedoil]

my 88 NA Supra, whenever I accelerate full throttle, like entering a fwy, it "bogs"/Putters" when the motor reaches 4200 rpms.

I dont have any codes. What could this be? I recall once forgetting to put the dipstick in the dipstick tube and the car motor would stall at a stop light, once i put the dipstick in the dipstick tube it ceased doing that. With that being said; I noticed the dipstick tube housing was loose and easily came off. So I put silicone around the rim that enters the motor and the seal slightly improved the puttering upon full throttle acceleration but the car still putters" and gets stuck" at around 4200 rpms...???

[RyanDronsfield]

Originally Posted by forgedoil

my 88 NA Supra, whenever I accelerate full throttle, like entering a fwy, it "bogs"/Putters" when the motor reaches 4200 rpms.

I dont have any codes. What could this be? I recall once forgetting to put the dipstick in the dipstick tube and the car motor would stall at a stop light, once i put the dipstick in the dipstick tube it ceased doing that. With that being said; I noticed the dipstick tube housing was loose and easily came off. So I put silicone around the rim that enters the motor and the seal slightly improved the puttering upon full throttle acceleration but the car still putters" and gets stuck" at around 4200 rpms...???

Sounds to me like it could be meany things ur car is natraly aspirated but still relies on a vacuum to do such tasks as regulat fule presser, I'd start with that then check ur ignition (spark plug spark plug wires distributer/coil pac and timing) a nother could be ur fule filter.
Those could cause hesitation/bogging but in a natraly aspirated engines I haven't seen it happn in such heavy symptoms I'd sugest there be multiple problems.

Mine only has hesitation sometimes and only in the lower rpm band ( so no building boost)

[cre]

Ryan, the Code 11 sums it up pretty thoroughly... Actually depending on how completely it's losing power it could lose the stored codes too. The TSRM specifies what you need to test I believe but here's a quick list:

100A Fusible Link, EFI fuse (just replace it), Circuit Opening Relay, EFI relay, clean and tighten the EFI/ECU grounds (connected to the intake manifold toward the rear) and make sure it's mounted securely.

Here's the wiring diagram so you can see how it is all connected:
http://www.cygnusx1.net/Supra/Librar...px?S=Main&P=46



Forgedoil, look in the MKIII FAQ section for details on checking for diagnostic error codes and pot back in a new thread. Posting about your vehicle's problems in someone else's thread while they're still actively trying to fix it usually only causes confusion as your issues are not likely to be related.