I just finished installing my LT8S standalone harness into the car, previously it had the adapter from the stock engine harness to the LT8S. I thought I had done everything correctly but now i don't think so.. Heres the issues at hand:

Don't know if its ignition breakup or what but it starts backfiring as soon as it gets about 3k? i've tried turning down when the secondaries come on but it makes no difference?

After connecting the connections back to the Guage cluster the rpm/speedo gauges move in sync and pretty close to the RPM displayed on the microtech

I can provide all numbers accept those from a wideband as i don't have one?

The map thats on it now has worked perfectly till about a week ago, when i blew a reley or fuse or something in the car.. couldn't get power to the computer so i decided to install the standalone harness... Any help would be appreciated as i am in Alaska and we know how few tuners their are up here, thanks

 

something else i've found with playing around is that the ecu gets error codes on the RPM and the TPS? when the car is at idle its shows the IDLE map or otherwise it sits on the TPScal map? could the settings for the TPS be wrong? i used the S6 wiring off microtechs website for the TPS

 

For your tps. With the car off and in reds.

It should be 0% with no throttle and it should have a * showing up in the second line.
Then when you flatten the throttle it should go to 99%.

Your rpm error is from bad signal from your crank sensors.
Check that you have NOT grounded the shielding in the CAS wire and make sure that any uncovered areas have been wrapped with aluminium foil is shield wire.

 

hmmmm k well i did have the shielding grounded as the wiring diagram shows it as being grounded? maybe i'm reading it wong but thats what i see, i'll change it and see what happens

 

It will be grounded on the ecu side if your using a proper microtech loom

 

Well the RPM error went away, but i still a TPScal error code still, its weired once i start the car it doesn't display any errors but once i rev it a couple times i get the error? I'm correct in assuming that theirs only one groud off the harness and thats directly from the ECU correct, and the CAS? are their any voltage tests or anything that can be done somewhere?? what kinda numbers should i be seeing at the coils? just a little "Lost" thats all

 

Ok rpm error is gone. That is good.

Where are you checking for error codes?

Have you checked all your earths?

 

I've checked the grounds from the ECU and the CAS those were the only ones that i had to do when installing the harness.

 

WOW... ya know sorry guys i'm an idiot... after looking at the diagram for the 12th time i see it says "looking at the sensor" i wired it looking at the plug, so i be my connections are backwards.... very sorry for your time guys, i'm gonna switch them around and let you know if it changes anything

 

Well after pulling the heat shrink off the wires and undo'n the loom, i did have them hooked up correctly. By using the Software i can see that the TPS is at 0% at and when you press the pedal to the floor it goes althe way up to 100% so to me that means its hooked up correct right???

 

Well after a little more testing i've determined that my car starts without the TPS connected??? i took some voltage readings before i started the car and with it in Ign on not started i had 5v to Blue and Gray wires at the tps, and i had 10.3X volts at both sides of the Coils... the Tach output wire gets about 10v when the car runs an doesn't vary much with revs? The grounds i've checked are off the block by the CAS sensors, battery ground, and the ground on the top of the LIM, my ground also to the Greddy profec B. I'm having trouble wiring my A1000 Fuel pump as well, but it comes on as soon as you turn the key to Ign on without any of the sensor wires connected.... are their two different types of ignition on sources? switched and constant? what could possibly be feeding voltage to my gauge cluster tach/speedo, when i rev the car my Speedometer goes up? turn the car on and its goes to 20mph... it didn't do any of this last week when i was hit'n around 24psi????

 

So does the Microtech have a Base map that it uses to run the car when the TPS isn't connected? I'm to beleive that it must use adefault map when the ecu enters this state?

 

Well i tried to incorporate the wiring diagram i received with my Fuel pump controller and HKS twin power but i can't upload it cause the files to big and i can't resize it.. So i ran some voltage tests today and heres what i got

Car in Ignition/NOT RUNNING

12V at Primary and Seconary injectors
12V at the coils on both sides of the coils +/-
Blue/Yellow wires from the CAS are grouned
One side of the Coolant sensor is grounded other side has resistance
with the TPS disconnected and IGN on but not started the TPS has:
0V on the ground, has good ground
4.92v on the Grey wire
4.92V on the Blue wire

I did however manage to shock the crap outta myself when removing the spark plug wire off the leading side and attempting to put it on! and by this i figure that with the ignition on my coils are firing.

All of this is with the TPS unconnected and the car not running!! does this help out????

 

There isn't a base map that it uses when the tps is not connected. I am assuming it is running off the idle map as it has similar injector times from the the factory for different loads

 

K so then this is a normal function then, if the computer loses the TPS signal it just goes to the idle map.. Now if i reconnect the TPS sensor it runs a little different but not alot... i still have all the same problems though

 

K so after a little bit more work.. i noticed that with the FP at 40psi 2600rpm.. 60psi it was at 3200rpm... and at 20psi it was at 2100rpm??? any thoughts?

 

Your fuel pump isnt wired properly or is wrecked.

 

Its wired through the Aeromotive Fuel pump controller, the Fuel pump its self is good... Those were made at the FPR inside the engine, both pump and contoller can support those numbers at under a 3k load easily.. Aeromotive A1000 with the billet aluminum Fuel pump controller

 

**** off the fuel pump controller.
Wire it through the microtech like it should be.
Your break up issue will go away as soon as you wire up the fuel pump properly, and set the fuel pressure correctly!

 

K so to do that, i just need a standard 12V relay? I don't have any of these so just a basic one will do? I will i'll try this without the controller and see if i get any different results. thanks

 

So i added some grounds to the engine, i ran a direct wire to the ground for the CPU, HKS twin power, one to the block of the motor and one to the Front of the UIM, also leaving the one from the firewall on the other side. still no changes fuel pump is wired for just 12v so when the cars on its gettin max voltage, FP is constant and doesn't vary but 3-5 psi... Also something that i have noticed is that when i Step on the Gas pedal, my Tach/Speedo zero out, when i release the Pedal the tach goes to about 1000 and the speedo to about 25mph, keeping in mind that the speedo /tach arn't connected to anything accept the dash, tranny's not connected and the tach signal isn't connected.... Anything else anyone can think of????

 

Sounds like you have some wiring issues.
ID remove the microtech loom.
RE wire it from scratch. THAT IS EVERYTHING.
CAS, Injectors, Coil packs. And dont connect anything else to it(i.e tacho).

Work from their.
Im not familiar with the HKS twinpower. Is that some sort of ignition booster?

 

yeah gonna pull it out this weekend and rewire the whole car... definitly have some grounding issues i beleive/relay problems sooooo... yeah when i get things back together i hope i don't have the same problem... thanks for the help guys i'll be back later!!!

 

well i decided to try to do a little more figuring before rewiring the car... I had some friends over to help look at things and we took a video, it'll be up either today or tomorrow, i don't think it will be very long but plz look at it and lemme know what you guys think it could be?

 

http://www.youtube.com/watch?v=Insg0jpxCFE Heres the video we took yesterday, any thoughts????