Car starts on CSI but wont hold

[Merlyn]

Ok, this is not the normal, OMG I came home from work and it won't start, where do I start looking for problems... this is more like, I have 2 mechanics and myself, and we are running out of options and we need help

So far we have replaced

ECU
Bad CPS
Bad Coil Pack

We Know
Fuel Injectors are getting power but not being told to fire
ECU is NOT Bad
CPS Is NOT Bad
We Have spark
We have fuel pressure
The car is timed
There is continuity between ECU, CPS, and Fuel Injectors
Car has fuel
temp sensor is functioning
and probably some other things I can't remember

simply, we turn the car, the cold start injector will start the car, it will idle for 5 seconds and turn off. We replaced a bad Coil Pack and a bad CPS and they have tested to work. We are running out of options, the only thing we have not tested was the MAF because we unplugged it and the car would not go into limp mode or respond any different. We have checked most of the wiring around the area of ignition and fuel, we have tested just about everything we can and the car will not start, does anyone have any idea what the problem is... simply this is a break down of the "equation" that we believe we had fixed....

ECU tells fuel injectors to fire based on the CPS
ECU was replaced even though it worked
CPS was replaced as the old one was bad
fuel injectors are able to fire manually and are functioning...


there is not much more we know to do... Please only contribute if you have something to contribute, we have spent a month working on this car on and off and we are about at our wits end...

 

[3p141592654]

When you say the injectors are not firing, is this based on an electrical test or an audible test? If electrical, have you confirmed 12V at the yellow (or blue or red) wires of the injector plugs with the plug disconnected and ign on?

Have you tried jumpering the fuel pump on at the diagnostic block (FP to E1) and trying to start it?

 

[3p141592654]

I guess I have two points:

1) Are you 100% confident the injectors are not firing, and how did you come to this conclusion (specific tests).

2) If yes to above, first thing to check is if power is getting to the injectors. This is an easy test with a voltmeter. Pull an injector plug, turn on the ign, and check for 12V at the yellow, red or blue wire (depending on which bank you are looking at).

 

[Merlyn]

I was not there for the test on the injectors (the car is at my mechanics I stop by once a week and we work on it for a few hours) I was however told the injectors are not firing, they can be manually fired, but they are not being pulsed to fire. Simply, these tests I was there for should verify...

1. We have fuel and we know that
2. The car will crank 4 - 5 times and run until the car has warmed up (meaning, it will turn on for the CSI for a few seconds)
(Cold start injector does not function on a warm start), so for the car to be able to run on the cold start injector, then it is getting fuel, but not able to run on the main injectors, unless the fuel rail itself is bad, or all 6 injectors are bad... we are getting fuel to the injectors. I would have to ask my mechanic, but to say he is 100% correct, as everything I have questioned him about he is able to pull a multimeter out and check and prove to me that he is right...

the injectors are NOT firing
cold start injector IS firing
we have fuel

and now we have code 14 back after replacing the CPS and the bad coil pack

 

[Merlyn]

Code 14... the car is starting... for a few seconds... like the minute it actually starts to fire he dies... gets to about 1500 and as fast as it gets to 1500 it dies... we have oil burning out the tail pipe (bad turbo) the car is pushing fuel through itself...

I had code 14 before, when I first got the car and replaced the coilpack, it went away, now it is bad, we replaced the CPS and the coil pack, we have spark, now I have not checked spark since I noticed code 14, but to say that something went bad in 1 month without the car even running kinda confuses me, only other code is o2 sensor as we have that disconnected..

 

[Merlyn]

I understand the aspect of code 14... but aside from code 14, because we have had this problem before without code 14, so I highly doubt the problem is related to code 14 as the symptoms have been the same from day one..

is there anything else you can think of

I know code 14 would cause it not to start, and realize why... but at the same time...

if I was showing code 14, replaced coil pack, code 14 was gone, and I cranked it the minute I saw code 14 gone, and it was still gone, same thing as now is happening with code 14, so I know the issue is not code 14, maybe we are not able to "fix" the car without fixing code 14, but there is obviously somethign else wrong besides code 14, after code 14 is fixed, and the problem continues, what do you recommend.

 

[3p141592654]

Ahh codes... now I had assumed since this problem has been worked for some time that any codes were long ago cleared.

You need to fix the 14, no question about it. Based on your initial post this has all been checked, so how can this be? Something is not quite adding up here.

By the way, a 14 is fatal, so there is no point trying to proceed until it is cleared, even if you feel it is not the root cause. That engine will never run as long as that code 14 is there.

As JJ points out, the CSI is energized by the starter circuit. It goes dark the moment you release the key. So, is your momentary idle consistent with a shot of fuel that stops as soon as the key is released?

 

[Merlyn]

as stated... 14 just came back... all the other tests were run before 14 came back, 14 came back just today...

 

[3p141592654]

Lemma: You never really fixed the code 14. You thought you did, but clearly you did not or it would not be back.

Check the igniter circuit per JJ's instructions.

 

[Aspec]

as stated... 14 just came back... all the other tests were run before 14 came back, 14 came back just today...

So whether or not it was there before is irrelevant. It is there now (see every BHG denial thread and how they end) and must be addressed. Does it suck? Yup. Does that change it? Nope.

Now. . . If when you say you checked everything (wiring) involving fuel and spark you meant you or your mechanic ran every circuit for continuity, then everything was not "tested". It only takes the smallest connection, 1 strand of wire, to get continuity(shit, i've seen a small air gap show continuity). Back probe the circuits to the ecu, check for the proper signals and you will be golden. Chin up it's only wiring.:icon_bigg

 

[Merlyn]

the noid light was one of the first tests we did, I stated in my first post, I forgot some of the diagnostics we ran, and yes, I plan to clear code 14, leave it at that, my mechanic asked that I ask one question on here, I put as much detail as i could to get answers

"What would cause an injector to be powered but not have the signal to fire from the ECU without Code 14 showing (as it had not shown before today)" that is the question

without code 14 in your heads, a clean ECU as it has been for 3 weeks

what would cause the injectors to not fire...

 

[IJ.]

No matter what it had before it NOW has a code 14 and will NOT run again until you correct whatever is causing it.

 

[jetjock]

Lets just call it my mistake for trying to help and chalk it up to experience .

 

[Merlyn]

Sorry for getting frustrated...

I just spoke to my mechanic

I asked him about his diagnostics ect and they were legit (fired an injector with readings of fuel pressure, fuel pressure went down when the injector "fired")

I told him there is no use looking for other problems until code 14 is fixed so he is going to take a look into that today

Thanks for the help jetjock, I guess the frustration of the car got to me, and I wasn't using my own basic knowledge... fix what you know is broken before you say something else is broken.

 

[Dunckel]

I (with JJ's help) just cured my 14. Turned out to be a bad ignitor. I had the same problems you describe.

 

[jetjock]

Hey, it's OK Merl. I know how frustrating things can be. My computer makes me nuts at times but it'd likely be a cake walk for you. Thank God the stuff I fly behind doesn't run on Windoze.

So he did injector pressure drop tests? Appears I may have underestimated the guy after all. My bad. That's good basics but it's still not going to help with an ECU that'll refuses to ground the injectors until it receives IGf. Get that straightened out first and go from there. Based on what you posted and our little chat offline there shouldn't be anything else stopping it. Well, not anything else that shouldn't be simple to track down.

Assuming timing is OK a no start on a 7M should be troubleshot by fuel pressure first, spark second, and injection last because without spark there can be no injection beyond a few seconds of starting. A bad circuit opening or fuel pump relay could somewhat mimic your symptoms but that'd be readily evident in a loss of pressure after start.

He may want to look at fuel pressure or fuel pump voltage during that time. If the engine won't run with the fuel pump jumped in the diag block that'd be a waste of time but if he's trying to start with the pump under ECU control it's worth checking after the code 14 is fixed.

Ask if you need something more. If not let us know how it all turns out.

Dunckel: Dead in the water ones are easy. It's the intermittent 14 where the engine continues to run that drives people crazy.

 

[Dunckel]

Dunckel: Dead in the water ones are easy. It's the intermittent 14 where the engine continues to run that drives people crazy.

Mine was very intermittent. It would go days without any problems. I figured since he has replaced the coil packs, and the ecu already, there could only be one thing left. (for the 14 issue) But, I could be wrong.

 

[suprahooked]

Just a thought possibly a ignitor ground. The ignitor is ground through the case of the ignitor ,sand the area where it bolts down and bolt it back down.

 

[jetjock]

Doesn't jive with his symptoms. An ungrounded igniter won't produce spark because there's no ground path for the coil drivers. He claims to have spark so the igniter must be grounded. Improved grounding for the igniter is a good mod though. Mine has the internal ground brought out to the battery negative. Same with my ECU grounding. Imho Toyota drop the ball in both cases.