Camry dies after 15 seconds

[Handsonmaxima]

When i first started the car up, it idled like a champion at 3k. then i reconnected the EVAP and tightened up the throttle body. it idled at 2k, then went to 1.1k. now it dies if the car runs for more than 15 seconds.
all the wires have the correct homes, when the car idled at 3k it was smooth as silk, not even a hint of a miss(open headers made any fluctuation obvious if there was any.).
exhaust is now hooked up, all injectors are firing, and spark plugs are working, i tested all of them for correct timing.
when i rev it up with the MAP connected it hits 2.5k and rev limits, when i disconnect the MAP's vacuum line and i try to rev it it immediately dies out and i hear exhaust popping
I have the Air assist hose unplugged at the moment.
its a 98 camry with CPS ignition.

i cleaned out the egr with a small screwdriver and got all the crap out and i hear that can cause bad idle.

thanks guys i really appreciate any help anybody can give. i have an engine code but i cant check it because i dont have the axles bolted up yet..

[Mister_Perkins]

What did you do prior to it starting to run crappy?

[b2p1986]

This is totally a shot in the dark but it could be that your IAC (idle air control) is also all clogged up causing the car to inevitably die. I would try looking in that area first to see if there's an issue and possibly run some seafoam through your brake booster (just as god measure to clean inside the motor), try that and see if anything improves.

As Mr. P said though, it seems maybe you were playing with something prior to having this problem and you maybe didn't hook something back up?

[Handsonmaxima]

Originally Posted by Mister_Perkins

What did you do prior to it starting to run crappy?

well it never ran right, i put the engine in, it idled at the 3k. so i hooked everything up and now its impossible to get it to run for any length of time.

Originally Posted by b2p1986

This is totally a shot in the dark but it could be that your IAC (idle air control) is also all clogged up causing the car to inevitably die. I would try looking in that area first to see if there's an issue and possibly run some seafoam through your brake booster (just as god measure to clean inside the motor), try that and see if anything improves.

As Mr. P said though, it seems maybe you were playing with something prior to having this problem and you maybe didn't hook something back up?

the new motor has 103k on it and i rebuilt the head. so the whole thing is clean as a whistle.

the IAC is the one with the coolant lines on these cars correct? i might try adjusting the manual adjustment on the TB to see if it can stay alive, but the way its idling perfect for a bit, then just dies immediately has me ohming out every sensor i can find a reading for.

[Mister_Perkins]

Are all of the grounds connected?

Almost has the signs of a bad crankshaft position sensor

Are your Vacuum lines hooked up correctly? you may want to double check them

[Handsonmaxima]

Originally Posted by Mister_Perkins

Are all of the grounds connected?

Almost has the signs of a bad crankshaft position sensor

Are your Vacuum lines hooked up correctly? you may want to double check them

grounds and vacuum are all correct, when it idled at 3k i let it run for about ten minutes so i could check my oil pressure and my coolant temp and fans and look for leaks, everything ran golden, then i reattach the EVAP and put on the intake snorkel and bolted the TB down tighter, and now it wont idle and keeps dying, so something happen when i put the car together that im not able to figure out.

its funny you mention that, because i used the old crank sensor that was on the junkyard motor, i kept the one that was on the stock motor just in case, would there be a difference between the 99 cali celica CPS and the 98 federal camry CPS?

Im skeptical that i have the vac lines wrong, but its possible that since it idled so high before i just didnt notice the leak, ill have to check those tonight when i go over to work on it again, its my GFs birthday present and ive got 6 days to get it running and cleaned up to give it to her. so im down to the wire a bit here, thanks for helping me out.

[fenixus]

my old '92 buick tended to die after 15 mins from start (either cold or warm) and unable to restart when it developed a bad crankshaft sensor. once it died (usually while driving) I had to coast it to the shoulder and let it sit for 15 mins until I was able to restart the engine.

perhaps the sensor wire is damaged?

as above, make sure the IAC works right, check resistance on terminals when cold or go ahead and unbolt the TB and remove IAC for cleaning (get new gaskets ahead).

why was it idling at 3k rpm before? was it caused by an improper vacuum routing? are you 100% positive the vacuum hosing is now plugged in all right and all hoses are good (both non-restrictive and vacuum tight)?

any CEL? misfire? timing good? are you getting strong spark and fuel?

try unplugging the upstream oxygen/AFR sensor and try starting the car in limp mode (ignores most of sensor inputs).

another idea (rev limiting) could be a clogged exhaust?

[Handsonmaxima]

perhaps the sensor wire is damaged?
possible, as i said it was a junkyard motor, i need to find the OHM numbers for it and ill move the wire around and see if it effects the reading.

as above, make sure the IAC works right, check resistance on terminals when cold or go ahead and unbolt the TB and remove IAC for cleaning (get new gaskets ahead).
ill have to find the numbers for ohm.

why was it idling at 3k rpm before? was it caused by an improper vacuum routing? are you 100% positive the vacuum hosing is now plugged in all right and all hoses are good (both non-restrictive and vacuum tight)?
it was probably idling so high from the TB not being connected/relearning to idle after having been battery-less for a month
any CEL? misfire? timing good? are you getting strong spark and fuel?
spark is great, timing was done twice just to make sure. and i have fuel, i pulled the plugs with the ignition off and they were soaked in fuel when i cranked it. no misfire
I DO HAVE A CEL, i cant check it though because i cant figure the codes out without a code reader.

try unplugging the upstream oxygen/AFR sensor and try starting the car in limp mode (ignores most of sensor inputs).
it will start in limp mode if i disconnected the #1 o2? or do i have to unplug anything else.

another idea (rev limiting) could be a clogged exhaust?
If worse comes to worse ill unbolt the downpipe and try running it again that way.

[Handsonmaxima]

More diagnosis time
Crankshaft sensor has been tested good
timing was rechecked
vacuum was checked via perkins sticky
Started car with o2 disconnected
cleaned IAV by taking it fully apart and reassembling it.(F(*& those stupid soft screws.)
So by that time the car was starting to idle better, so i quickly gave it some revs, and it stuck. idled perfectly, it didnt move from 900 for 20 minutes.
so i told my gf her car was good to go and she went to take it out, and it wont idle again, so i kept it alive till it got warm and it idled fine.

so, runs perfect at 900rpm when warm, fans still do not turn on when hot so it will overheat, dies immediately if i dont have the gas pressed when i start it when cold, if i give it gas it will go to 1100, down to 300, back to 1100, then die.

any input?

[hardtopte72]

Sounds like either you have a vacuum leak (maybe from when you re tightened the throttle body), or an intake manifold, or a hose. Or the IAC or EGR valves have failed or are still dirty. There is a good way to check the EGR valve but I would have to be at the car to remember.

I would lean at this point to a vacuum leak since you said all grounds are good as well as the sensors. Also it is possible the crank sensors are different. Especially between JDM and American build cars.

The old carb cleaner around the intake should do the trick in helping you find the gremlin if it is vacuum related.