so i just did an ls motor swap and before i was having injector problems but i got that fixed then it wouldnt start unless i cover the tb but thats fixed, i think.

so now i got the car idling fine at 700 but when i rev it, it only revs to 1500 then it just loses power and drops back down and sometimes stalls if i stay on the gas and if i get off the gas the idle will stablize. there are no codes. i used a timing light and it was all good.

anybody got any suggestions and whats wrong

 

oh i forgot to mention that when it hits 1.5k it starts to backfire or hit a rev limit or something that causes it to pop and then it loses power.

timing issues ? timing light on the crank shows that its timed good

 

u have the wiring wrong on the dpi to mpi

 

what do you mean, plz elaborate ? dizzy wiring or ecu wiring ?

oh and before when it was running on only 2 injectors, it use to rev to 4k and start to lose power and start popping there

 

3-4 k is ecu limp in mode
so u had a bad ecu

most of the time its just dizzy wire thats wrong
u probably have cam and crank sensor wireing mix

 

does it matter that its 1.5k and not 3-4k ?

 

yea it does
it means bad wiring on dizzy to ecu

 

soldered all wiring between dizzy and ecu, still only revs to 1.5k

im getting a code 1, would that cause it to only rev to 1.5k ? if not do you have any other suggestions on what i could check

thanks i really appreciate your help, this has had me stumped for weeks and i need my car running

 

bump

 

check if your camshaft timing is timed w/ the crank, the motor can still run fine at idle but up higher it can't w/ the timing off. recently I had my cams 180 degrees off w/ the crank died on and it still ran and idles fine but drivability is crap. so make sure. another thing is check if your spark plug wire is in the right slot.

 

just checked cam timing yesterday, all good. shot my timing light on it and put it to 16 BTDC. quadrupled checked my spark plug wires

does it sound like a timing issue or more air/fuel problem ?

just to remind, at 1.5k its not hitting a revlimiter, the rpms just drop like i let off the gas or something, it just loses power

 

did u check the wireing at the ecu?
i think u got one of those dpfi to mpfi wireing thats wrong

Pins B10 and B12 are empty. Unused pins can be taken from B2 or B11. Sometimes there is a unused wire at B12. Cut orange and white wires off at C1 and C2 and connect them to wires added at B10 and B12. Orange-B10. White-B12. Leave enough wire for next step.

Run wires from C1 and C2 on the ecu into the engine compartment. Label these wires for later use. Cut wires at A3 and A7 leave excess for later use. Run these wires into the engine bay and label them to be used later on .


Under the Hood

TPS and EACV plugs are too short and must be extended. Be sure to switch green/white and yellow/white wires on TPS since the dx turns the opposite way.


Injectors and injector resistor box

Connect the yellow/black wires from the two DX injector harnesses and run it to the yellow/black wire on the injector resistor box. Connect the yellow wire from the DX injector to the #1 injector (brown wire). Connect the red wire from the DX injector and run it to the #3 injector (blue wire). Connect the A3 wire to the #2 injector (red wire). Connect the A7 wire to the #4 injector (yellow wire). Connect the 4 red/black wires from injector resistor box to each injector.

Cylinder position sensor

Connect C1 to blue/green wire on cylinder position sensor plug. Connect C2 to blue/yellow wire on cylinder position sensor plug the rest of the wires are color matched for your dx to the si wires

THIS INFORMATION IS FOR RESOURCE AND PERSONAL USE. I AM NOT LIABLE FOR ANY DAMAGE TO YOUR CAR OR OTHER PROBLEMS RELARED TO THIS CONVERSION

TEAM P IMPORTS 2002

 

here s the link
http://www.geocities.com/teampimports/fuelinj.html

 

k i double checked my mpfi convertion wiring at the ecu and everything looked good, everything was in the right place

does it sound like a timing issue, or fuel issue ? like i said not hitting a revlimiter, just loses power at 1.5k

possiblely bad o2 sensor ? would that cause it ?
bad dist ?

the ecu was run in my friends car but that was like 3 years ago

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by civickiller &raquo;</TD></TR><TR><TD CLASS="quote">k i double checked my mpfi convertion wiring at the ecu and everything looked good, everything was in the right place

like i said not hitting a revlimiter, just loses power at 1.5k

</TD></TR></TABLE>

how about when u floor it
switch ur tps and map senor plugs around
u may have backwards

 

they are not backwards because this tb didnt have a map sensor on it so my map sensor is on hte firewall running off a vacuum hose. but i do have the map vacuum and the fpr on the same vacuum line, could that be it ?

it idles at 700 and when i floor it the rpms drop down to like 100 and jump up and down like surging between 300 and 100 and if i let off the gas the idle will stablize again but down at 500 instead of 700. sometimes it dies

 

no the vaccum routeing is fine

try reving ur motor with tps unplug
if its fine then it wired wrong

same as 4 map sensor
(have to floor it to start with map unplug)

 

i unplugged the tps and the idle dropped from 700 to 400 and as soon as i stepped on the gas it died.

the map sensor was working with the old motor, think it would go bad?

the one thing that im worried about is the o2 sensor, im getting a code 1, i have the o2 sensor up near the head because the exhaust mani is from a obd0.
would the 4 wire heated o2 sensor being that close to the head cause a problem like this ? causing it to read too rich or lean ?

do you know how to fix a code one, i followed my chiltons manual and it brought me to a code 43 and then follow that, the book said "go to fuel system supply" and thats where i get lost because idk where in the book to find that

 

Do you have a fuel pressure guage?It will idle on a few pound but won't rev that way.The o2 sensor won't have this dramatic effect even if its completely dead.
Glenn

 

no i dont have a fuel pressure gauge

 

Its not a bad ecu, nor a bad distributor. Will rev to 2k only when throttle body is covered with a metal plate other then that when you try to rev it, it will just die.

 

yup spoon_fed was helping me and we found out that if you cover the tb completely except for a couple 3/32 drilled holes in the plate it will rev up to 2k and it will hold it if we floor it and it wont die or go higher. but as soon as we remove the plate it will die or try it without the plate it will die

 

i got it reving higher by using larger drilled holes up to around 5k but pretty much anymore air i let in will stall the motor

 

it won t be the o2 sensor u can unplug it and the car will idle and run fine

did u try leaving the map and tps senor unplug and starting the car (u have to floor it to get it started)

 

both at the same time or one and then another ?

do you think my obd0 firewall map sensor might not be reading as good as say a map sensor thats on the tb ?