ok....heres what happen....car was running then all of a sudden starting missing. I stop the car pulled over checked stuff.....found that the temp gauge was reading really high.....265 temperature.....Shut car off....tried starting after that point....no go....haven't been able to get it running...car cranks...but will not turn over.

I had a custom chip in it.....replaced it back out with the original chip....still same problem

I have spark at the plugs and have voltage at the injectors

I checked the valve on the fuel rail and fuel came through when tried to start the vehicle

I checked for codes on the ECM...none....blinks code 12 3 times and goes away...

BUT!!!...i disconnected both the Thottle Position Sensor and the MAP sensor to attempt to get a code to be thrown.....checked the ECM with my code scanner and again....just code 12......reconnected things back together.....so.....Iam very much lost right now...

I also have already replaced the cap, rotor, upper coil, lower pickup coil, ignition module....still no luck

anybody have a clue what to do?

thanks

jeff

UPDATE: rule out the cats....brand new Y-Pipe and front cats put on last fall. Main cat was replaced in the spring last year...so less then 10,000 on it.

Checked for water in the oil...none....
Removed plugs...no water leaking out the cylinders
Checked coolant level....level is fine

Started cranking over car while testing injectors....voltage at the injectors

Tomorrow going to double check ECM connections and wires....Haynes manual is really pressing toward a D3 or D9 failure....and since these two wires run to two different places (connectors) on the ECM.....Iam swaying toward a bad ECM.

When I shut the car off after noticing the high temperatures....I checked and the coolant fans were NOT running.....the coolant was NOT overflowing either or even high in the bottom white reserve tank....

so.....to review in the best order I can remember.

car started to miss or stumble when I just would touch the gas
car just felt wrong...like something was off
pulled into parking lot
looking at gauges noticed the temperature gauge to be very high 265 (my car normally never goes above 195 as I had a custom chip burned that turned the fans on at approx 175 and 190) Also I have a 160 degree thermostat in it. (been driving it this way for past 2 years)
popped the hood....noticed neither fan running
no visual problems with coolant system....not high in the tank or bubbling over
changed out: distributor, cap, rotor, ignition module, coil, pickup coil
checked all wiring and sensors
checked all fuses
ran code scanner....no codes
checked for spark...spark present at the coil and plugs
checked for fuel...fuel present at the fuel rails and tested the button on the rail...fuel shot out fine...plenty of pressure
checked voltage on the injectors.....voltage present
noticed the climate control for the ac is not correct....with just the key on turn the ac or heater on and not working correctly....air only comes out the defroster

I think thats everything I can remember.

Hope the extra information helps.....my next option is to buy an ECM from Mid America on Monday....so if anybody has another option or comment please feel free.

jeff :cool:


[Modified by XtremeVette, 12:34 AM 4/25/2004]

 

Wow, that temp is really high. I wonder if a head gasket went or something like that. Check for oil in the water and water in the oil. Might was to run a compression check or leak down test just to see what that was all about. Or maybe your timing chain slipped?

This is just a guess, but it might be that your ECM went bad, but that does not explain those high temps. I certainly do not recommend just replacing parts - get's too expensive.

Fuel + spark = :auto:

Good luck,

 

How many pounds of fuel pressure? Any chance the fuel pressure regualtor went kaput? Have you checked timing? Have you done a compression test?

Just curious....have you checked to see if the catalytic converter grenaded? The fact that the temps climbed so high leads me to think the converter disintegrated and clogged up.

Check these things and lt us know what you find out.

 

like the other one mentioned.... about the cats. Did you ever get your front y-pipe replaced? I know you had issues with it being clogged.

 

I updated my initial post.....

 

Engines need fuel, air, spark to run. Check the spark with a timing light and at the same time see if the timing is correct. You checked fuel pressure, but you should also see how long it will hold fuel pressure after the ign sw is off as a leaking injector will cause a rich mixture and will cause a rapid loss in fuel pressure. Put a low power 12v lamp across an injector socket and crank the engine, the lamp should pulse.

 

not the ECM.....i just got done changing it out....still no go!.....

hate this.....

 

Does your timing light flash and what is the initial timing? Did the fuel pressure hold when the ignition was turned off? Did the 12v lamp flash on an injector socket when cranked? Did you remove the flexible horn on the MAF to ensure the engine is getting air? Did you perform a compression test? Did you spray starter fluid into the MAF while cranking to see if it would fire?

 

Initial timing?...thought ECM handled this...before the problem...the timing was dead on.
when ignition off does not hold pressure. with ignition on fuel pumps out like no tomorrow.
Do NOT get a blinking light when cranked over.....test light stays steady....and seems to get slightly dimmer as engine is being cranked over then returns to steady on when stop cranking. I don't believe I have a MAF....as my car is a 1990 (speed density car) I did put starting fluid down the throttle body and the car did start up....so....its a definite FUEL PROBLEM. As stated I already changed both the memcal and the computer......does not fix my problem.

I don't have a fuel pressure gauge....so can't check the pressure...but I did hook a hose up to it and blocked it off with my finger....there was enough pressure there to force the fuel past my finger.

I did not do any compression test....as not sure why that would be needed?

So besides the ECM....why would the injectors not allow the fuel to get past them or why would they not open and close? very very lost!

HELP! :confused:

 

OK, you need to get a gauge on the shrader valve and check the pressure. Just because it will squirt past your finger doesn't mean you have the 40 PSI or so it needs to run.

I'm betting you have either a bad fuel pump or pressure regulator.

Since you have a new ECM, the injectors are probably firing OK, but did you verify this with a noid light?

 

yep, I agree on the fuel pressure guage...definitely gonna have to get one to verify pressure....

what do you mean by Noid Light?.....I checked the injector by disconnecting it and put my 12v lil battery tester light (looks like a small screwdriver with a lil fuse in it that lights up)

when cranking over the light just remained steady and dimmed a lil ....I put a multimeter on it and it started at like 10ohms and dropped down to 8 while cranking over

so hmmmmm I dunno....if Iam not using the correct light where can you get one....local autopart place like autozone?

*If the IAC went bad would this cause a no start condition?
*If the TPS went bad would that cause a no start condition? and most important....*If 1 or more injectors went bad, got stuck open or something else would that cause the rest not to fire at all? I mean I would think if 1 went out the rest would continue seeing that they are wired in paraelle to one another 1,3,5, & 7 on ckr 468 and 2,4,6 & 8 on ckr 469.

 

Your test light if you connected it across the two pins of an unplugged injector socket tells you that the ECM is not pulsing the injectors but rather is keeping them on all the time which floods the engine and preventing it from starting! You should easily be able to smell raw fuel coming from the exhaust when cranking. One terminal of the injector goes to 12v, the other terminal goes to the ECM which switches it to ground for a short duration at the right time to inject fuel. If the injector coil has an internal short, this should blow one of the injector fuses but it can also damage the ECM. NEVER install a fuse larger than the originals rating!!!
A noid light is a low power 12v light used to determine if 12v is present and intended to test for 12v pulses at the injector socket. I think your 12v test light is doing the same job! Also, just because you installed a brand new part (ECM, etc) does not mean that it is ok or didn't get damaged on the first attempt to start the engine. A shorted injector can immediately damage the ECM!


[Modified by jfb, 7:21 AM 4/26/2004]

 

ok....help me out now....trying to stay with you....especially JFB.

I don't smell any raw fuel out the exhaust at all.

No injector fuses have been changed and none are blown...

If your correct about the possible damage to the ECM....wouldn't I get a code 55 indicating it ? hmmmm

:crazy:

 

You may not get an error code for blown injector driver transistors in the ECM. Also, if the ECM does not get pulses from the distributor, or optispark, then it will not pulse the injectors, but if this is true then your test light across the injector socket will not light when you crank the engine. If your test light stays on the whole time cranking, then the injectors are held on and you will have a too rich condition preventing starting and you should be able to smell raw fuel coming out of the exhaust.

 

i here ya loud and clear jfb....just to be sure.....how exactly should I be checking the injector.....ground to ground and positive to an injector?

I will try cranking it again and smell for raw fuel out the exhaust like you explained.

I also did a test on the ECM....seems to be functioning correctly.....it is throwing 3 code 12's....then nothing.....

ALSO I went and put a different key in the ignition to trigger VATS and throw a code...the computer did see this and brought up a code 46 for VATS...

So what would you recommend from here....Iam going to check the injectors by disconnecting all of them and then checking them 1 at a time to see what kinda of OHMs they are reading....this is what my HELMS calls for next....

 

If you unplug each injector and measure the injector pins with an ohmeter you can only find gross defects in the injector coil. A much better test would be to use an impedance bridge and measure the inductance and the inductor "Q". I found one bad injector on my 87 this way, but I doubt you have access to an impedance bridge. If you are going to unplug each injector, I would test each injector socket with your test light and see if each one pulses when cranking. If no pulsing I would determine if reference pulses are coming from your distributor/opti. Let us know what you find.

 

thanks man for all the help up to this point...I will do exactly what you said and even see if I can't get ahold of that bridge through my father....

I'll get back to you ....

 

Excellent info from Jfb. You've pretty much got the problem narrowed down, now it's just finding out whether it's starving for fuel or drowning in it.

Were your plugs dry when you pulled them? If your injectors are hung wide open (continually grounded), they should be soaked with fuel (and you will need an immediate oil change once it's running) and you should be able to smell it.

It's going to be either a fuel pressure issue, or the injectors not pulsing correctly. Chin up.....you are verrrrry close to having this thing running. :cheers:

 

well frizlefrak....and jfb.....I agree...I think we are super close and have narrowed things down....but what troubles me is the fact that I still don't think Iam comprehending the real problem.....if the injectors are indeed hung wide open (continually grounded) which I think they are...seeings I did pull a plug and yes.....it was soaked with gas, then what does this mean? All 8 of my injectors went bad at the same time? that don't make much sense....or can 1 injector go bad to cause my no start condition? My manual doesn't say much about this.....I understand that I have a fuel problem....and appears to be a flooded or soaked situation....but how to correct this? Replace the fuel injectors....this is a very large and costly job.....that if is the reason...I don't mind doing....but if it is not....well I think you can imagine how upset I will be :banghead:

thanks.....hopefully tomorrow will clear enough that I can do some more testing on the injectors and smell for fuel while cranking her over.

 

All 8 of your injectors didn't go bad at the same time, all one of your ECM's went bad at the same time holding all 8 or your injectors on and flooding the engine. That is what I believe.
Or the wire going back to the ECM is shorted to ground (this won't hurt the ECM) holding all of the injectors on.


[Modified by jfb, 11:11 AM 4/27/2004]