Galant throttle issues

[suprakid94]

Hello guy, got a problem I'm trying to track down, I have #1510 and just picked it up from a long time friend...I've known this car for over 8 years, and finally ended up buying the car...here is the issue...car sat for a couple of years until I got it...put a brand new battery in it, and refreshed it, and starts and idles perfect....now the issue is under half throttle it will rev thru the powerband, but if you stab the throttle, it cuts out and will go no farther.....the previous owner said the alt died on the way home 2 years ago, and he put a used alt in it....so I let it sit for the night, and the next morning...battery is dead as a door nail...now its a brand new battery...he also has the battery in the trunk and made it so you can jump it from the front...and this is the kicker...it runs the same with the battery disconnected as when its connected....so I did a boost leak, and found 2 leaks...that have been fixed, yet it still is doing the same thing....I'm thinking its still the alt, although I have not tested the output of it yet...thanks to the weather...i'm correct in saying that dsm's hate not having a steady 12-13 volts at all times....so has anyone else come across this issue?

Thanks in advance to anyone that can help...if anyone wants to see a vid of what its doing pm me

Mod list is this, spearco front mount, HKS boz, 2g maf, full d/p and exhaust, and it did have some kind of tuning either software of chipped ecu, got the cable in the glove box...I'm trying to find out what it was from the former owner, and 510 or 550 injectors

Cheers
Marc

 

[AllanL]

try to lube the throttle cable and throttle body...

 

[tektic]

tps sensor would be my first guess.

 

[suprakid94]

Allen

Tried that already...nothing changed

New update The Ecu has a keydriver chip for the inj, airflow sensor, stutter box, and turns the factory boos gauge into a knock gauge...has selectable launch rpm by pressing the throttle before the car starts, it will bump up on the stock boos gauge, and the ecu is socketed---Key the car on without starting, and each press of the throttle bumps up a light on the boost gauge---when you start the car it saves the rpm until you turn off the car

The cable was for data logging, basically old dsm link, says I need to look for a copy of old dsm link software off dsmchips.com

Also the power/Econ switches between high and low boost through the factory bleed off solenoid . ECM can still reduce boost if it goes into limp mode

Maybe all that will help someone help me out on this one....

I've had dsm's for years...but that's been over 15 years ago, I'm a Nissan Specialized mechanic for JDM engines, so getting back in the DSM world has me feeling like a newb all over again...

 

[suprakid94]

tektic

Any idea what the voltage should be so I can test it?

Thanks for the help

 

[tektic]

The resistance should change smoothly without jumping around iirc

 

[ktmrider]

Check the wiring for the Stutterbox plus find out if it had NLTS ( No Lift To Shift ). When you state "half throttle is fine" what are the RPM's? NLTS usually limits revs to 4000 or so, if it's not hooked up properly it will be engaged all the time.

Ideally get a Logger setup for most all troubleshooting on these cars. I still see them on Egay for a decent price. Makes TPS check easy, should show between 9% and 11% at idle. Otherwise find and bookmark the DSM FAQ website for a ton of great troubleshooting tips and maintenance items.

 

[FlyingEagle]

Please don't disconnect the battery while the engine is running.

Massive voltage/current spike occurs in the alternator when that happens. Electronics don't like that much.

Loose battery terminals love to take out components for this reason.

Put a DVOM inline with the either the negative terminal or the positive terminal.

Check to see how much current the electrical system is circulating.

If you have a bad diode in the alternator/generator, you will have enough current load to suck a good battery dry in a few short hours.

Alternatively you can simply check for AC voltage across the battery or from the positive terminal to a body ground, and see what value comes up.

Anything near half a volt AC, is pushing the limits and doesn't really fall within the norm of DC rectified voltage, heck even something over .3V would be suspect.

Some cars have dirty voltage, mostly at lower RPM, but this is what I have found from checking many systems with flickering headlamps (traditional bulbs, not HID's) and or weakened batteries.