Posting my problem once again...

[venomceli]

I know I have posted this before but its getting really annoying and no one seems to be able to figure out what the problem is...

First of all this is what I am running:

2000 toyota celica gt
550cc rc injectors
255lph supra fuel pump
c2power st1 kit with large intercooler and kkk04 turbo
greddy emanage
custom 2.5in exhaust
zeitronix boost / wideband AFR guage
boosting at 10ish psi

This is the problem im having...

when full throttle everything is fine.. The afr is at around 12

idle is also fine, maybe a little rough at times but never stalls or anything..

Its when cruising at a constant speed/rpm it seems to give me problems

for instance, everytime I start my day and get into my car I have to travel down this long dirt driveway.
I usually do this in 1st gear at around 2-3k rpm

so I hold the throttle so im at a constant 3k rpm and cruising down the drive way... Then all the sudden the car reacts as if I take my foot off the gas pedal!
(and I dont ofcourse).. Then the rpms proceed to go down to about 1k-ish then the car jerks and goes back up to 3k rpm

( all this happens with my foot still at the same position on the gas pedal as it was at 3k rpm, i dont let off the gas at all)

This happens all the time no matter what gear, just when at a constant rpm, (no matter what rpm)

The afr reports around 14.7ish +/- afr at the time so that factors out a tuning problem..

This has been going on for over a year and its really annoying, any help would be greatful.

-Todd

[Hetts]

Your spark plugs gapped correctly?

[JayHass]

It's a problem between the Emanage, larger injectors and the stock Toyota ECU. I've seen this problem first hand and had some reports of it as well.

Granted you don't have an exact replica of our kits so the fix might not work 100%.

Basically, this is what's happening. The stock computer turns the injectors off at zero tps when you are off throttle and turns them back on again at 1400rpm for idle. This is in the FSM so don't think I'm making it up...

For some reason with the larger injectors, the car kills the injectors at about 2-3% throttle and not zero throttle. Next time your car does this, just push the pedal down a hair and it should snap back to life. If so, that's the issue.

The cure we have come up with is adjusting your TPS to the max side of spec. In other words the higher voltage side of spec. This will give a little advanced signal to the ECU and help this problem.

The larger the injector, the worse the problem I have noticed so it's probably tied somewhere into the modified MAF signal for the injector correction. For the record the Emanage Ultimate when set up for a add/trim on the fuel injectors does not have this problem as it modifies duty cycle directly.

It could also be an over agressive anti-stall setting in the Emanage but I've never seen their maps to know if they activated that function and/or how they set it up.

Good luck.

(C2, hope you don't mind me giving advice for your kits I just have been down this road and wanted to help the guy out.)

[6speedGTS]

Basically, this is what's happening. The stock computer turns the injectors off at zero tps when you are off throttle and turns them back on again at 1400rpm for idle. This is in the FSM so don't think I'm making it up...


Nope, your not. I read about this function in a car review and the author mentioned that it made driving the car a little bit jerky when cold. It happens to me. The theory behind of it suppose to cut down emissions. Nice to know that it can be adjusted when tuning, now if we can just up the rev limiter.....

[venomceli]

"Next time your car does this, just push the pedal down a hair and it should snap back to life. If so, that's the issue."

Thats what I have to do to get the car to react....

"The cure we have come up with is adjusting your TPS to the max side of spec. In other words the higher voltage side of spec. This will give a little advanced signal to the ECU and help this problem"

How do I do this? If i recall correctly the way you set the tps is it tells you to let off the gas the floor it....

Thats for the replies!

[JayHass]

"Next time your car does this, just push the pedal down a hair and it should snap back to life. If so, that's the issue."

Thats what I have to do to get the car to react....

"The cure we have come up with is adjusting your TPS to the max side of spec. In other words the higher voltage side of spec. This will give a little advanced signal to the ECU and help this problem"

How do I do this? If i recall correctly the way you set the tps is it tells you to let off the gas the floor it....

Thats for the replies!

Not in the Emanage TPS setting but physically adjusting it at the TB. Hook up a volt meter to the output, measure it and set it on the max side of spec. (You might even get away with going past the max value and/or might have too in your case to fix this.) There are two screws holding the TPS in place which is slotted to move one way or the other.

That should take care of it or at least help a lot.

Good luck.

[venomceli]

Any pics on were this is and how to do it?

I just looked it up in the shop manual and it tells you how to test it with the ohm meter but not how to adjust it.

http://img.photobucket.com/albums/v222/venomceli/tbp_sensor.gif

Also what gap are the plugs supposed to be at? I just bought the gts sparkplugs for my gt and kept the gap like it is.

[c2gas]

Why I am confused about this that Venom is the only one who has this problem. Never ever expirienced it that baaaad on any other car. He used the same base map and tuned that.
No prob Jay ;)

[venomceli]

would it make a difference becuase my car was made in sept '99, thats gotta be one of the first ones right?

I tried testing the tps but i was getting craZy num bers, i think becuase i have a voltmeter? I dont know, i actually dont really know how to use it I guess, but i tried.

I looked at it and didnt see any way to adjust it.

[JayHass]

Any pics on were this is and how to do it?

I just looked it up in the shop manual and it tells you how to test it with the ohm meter but not how to adjust it.

http://img.photobucket.com/albums/v222/venomceli/tbp_sensor.gif

Also what gap are the plugs supposed to be at? I just bought the gts sparkplugs for my gt and kept the gap like it is.

It's super easy. You can't screw it up. Honest. LOL

Keep the TPS plugged in and put the DVM on the wires that give you voltage reference and not a feed. (Feed will be like 5V and reference will be like .5v or close to that range.) I can't remember if it's top and middle or middle and bottom...just poke around till you get the right voltage - it won't hurt anything if you are on the wrong connectors.

Note the stock voltage setting, loosen the two screws holding it on, and twist the sucker one way and then the other. You'll see your voltage change. Adjust the voltage higher. I *think* the high side of spec is .63v. Tighten down the screws and take it for a ride. If there is no change trying going a little higher.

You'll have to recalibrate the Greddy now that your TPS reads differently but that's cake too.

Gas: I have very few customers that have this problem but there are a few. I noticed this when screwing around and testing on the cars. I think it's a lot to do with driving style than anything. I've gotten in cars that guys say has the problem and didn't notice it till a drove a certain way. :crazy2:

[venomceli]

Well , i dont think its how I drive because it does it when the crusie contol is set as well.

THnx for the help though man, Im going to do it tomarrow, im glad i finally got a new idea to trouble shoot the problem~

[spookie]

I also have this problem and I also have the late 99 model.