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Need some help folks, car starts, runs, then dies

Lots more useful information there. I guess when I get home I'll have to just get in the car set up the laptop stand and the laptop and the scanner and sit in there while it runs and watch everything until it dies. Thanks for that tidbit Brian.
 


I've seen that with my own car - I had to lock/unlock with my "main" key and then start - then shut off. Then lock/unlock with the other key - then start. I may have completely lucked into that sequence.

My security light was not flashing - FYI.

-Swash
 
I wouldnt rule out fuel until you check the pressure. when pressue drops off...it will starve the engine.,...and will shut off...just because you hear the pump...isnt enough to rule it out. see if the pressure bleeds off. if it doesnt move on to other areas. if it does, you have your problem my friend.

Good Luck!
 
I see your point bud, but wouldnt the engine sputter and stumble if it were a fuel pressure issue? I mean the thing literally just stops running, like it was turned off.
 
Okay, well Im home, so Im going to turn on the WiFi, grab my DHP and go out to the car and do some monitoring....I'll try and get on IM too and hopefully I can get this thing nailed down.
 


Okay the scan failed. When the engine shut down, the electrical system reset (I assume it did cause I heard the fuel pump fire up again like you hear when you first turn the key to start the engine) and of course that freaked out AutoTap and it didnt save the file unfortunately.

I was sitting in the drivers seat and didnt see any lights on the dash (like the security light) there are no codes pending or otherwise. I dont think it ever got out of open loop mode, coolant temp was around 140* when it shut down.

It ran for about 7 minutes then shut down. I wasnt watching the AutoTap real closely because I was recording and figured I would have the data. I was more interested in anything going on with the dash lights.

So I guess Im going to have to see if I can dig up my fuel pressure gage or go get one if I cannot find it and start there. The whole running and dying thing has just got me trippin'. Ive never seen a car do that before. It just shuts off. Its like I grabbed the keys and turned the thing off. No stumbling, no hesitation, no warning at all. One second its running, the next it isnt.
 
my drag car did that. I didnt have the car tuned for the cam yet...and it didnt like to idle for more than a minute, but is nothing compared to you problem. be patient. dont overlook anything......you'll get it.
 
Hey Scotty,

The 2001 does not have a resistor....thats when they went to the venturi system in the fuel pump. I still think it has something to do with your sensors. Just based on what you have told me, the car shuts off when it starts to warm up......open loop vs closed loop....I may have this backwards since its late, but open loop is when the car first starts....it does not use any sensor inputs, but instead uses pre programed values set in the PCM. Once the car passes X (time vs water temp I think) threshold and starts to warm up it goes into closed loop meaning it quits using the pre programed values and starts using the sensors. One of the sensors I think is whacked and killing the motor. Your best bet is to look at the MAF first.

webracin
 
Is it strange that when the engine died all power died with it killing the scanner? I mean should the PCM still have power with the key in the position it was in when running? I don't know so curiosity makes me want to know.
 


After spending as long as I did in electronics, I tend to think its a sensor as well. At this time Im thinking is the Crank Position Sensor. It was pointed out to me that I 'should' be able to see some type of RPM signal when cranking the engine, but Im not after it dies. And I remember that the CPS will cause the Tach signal to die.

The problem is, I dont know if I have the tools to get the stupid crank pulley off. So Im going to have to look into that and see. I sure wish you didnt have to pull the crank pulley to replace that sensor or I wish I had an air compressor and an impact wrench.

I am going to check the fueling and spark just to be on the safe side, but my gut instincts is telling me its electronic and most likely the CPS. So we'll see I guess, Im not afraid to admit Im wrong if thats not it.

I think it was UR LOSN that suggested that it may be the maf. I do have a spare or two here, so I can do that just for good measure too.
 
Okay, I got a new snag, I think.

I have two spare MAFs. One I know to be from a 2001 because I bought the whole throttle body for it and it came with the sensors. I have another throttle body that came with all the sensors, but I cannot remember what model year now. I know there is some differences in the MAF in the 97, 98 years I believe.

The two spares I have and the one on the car have the same what I think is the part number:

AFH50M-05

But there is another number down below that that is different on all three. I think it may be a Serial number, Im not sure.

1. A0722 <--This one I know is from a 2001
2. A0922 <--Dont know what year this is
3. A0412 <--The one on the car

I gues its ultimately not a big deal since I know one of them is from a 2001, I just wanted to make sure the other one would be okay to use if need or so I could hook it up and make sure it works properly. Anyone have any insight?
 
Hey Scotty,

The tool you need to pull the Harmonic Balancer off is a Lisle 45300.

If you need it right now, they have the bolts at NAPA and its about 52.00 for the set

Part : BK 7002461
Product Line : Balkamp
Price : 51.99

223947.jpg


Or you can get the whole kit for 34.00 at SJ Discount Tools

webracin
 
LOL, the nearest NAPA is about 20 - 25 miles away from here. But I'll look for that in the stores around here. My big problem is getting that blasted bolt out that holds the balancer in.
 


SyntheticShield said:
LOL, the nearest NAPA is about 20 - 25 miles away from here. But I'll look for that in the stores around here. My big problem is getting that blasted bolt out that holds the balancer in.
Click to expand...

Clamp the vice grips to the flexplate near the block (front side of block) and use your breaker bar. Heat can help.

Effective but possibly dangerous, use a reasonable size cheap ratchet that is long enough to touch the ground. Remove the fuel pump relay, bleed off the fuel at the schrader valve, crank the engine to make sure it won't start.

Attach the socket/ratchet combo to the balancer bolt, wedge the handle against the ground and crank it over. The bolt will come loose.
 
Yeah, Id be a little, well, scared to crank the engine with a wrench on it. I did buy one big honker of a breaker bar at AutoZone tonight along with the CPS sensor. Problem is now I dont know what size bolt that is on the pulley.

I have a harmonic balance puller from my last GP but it was an '89 SE and only had the 2.8L V6. Is there something special about this balancer that I would need a special puller?

How do I get that sucker back on also? Just get it started and use the bolt to pull it in as its tightened down?
 
Scotty I would check spark when it dies before you swap out the crank sensor. If it is bad you lose spark and fuel both. Pull a plug wire off of any coil, put a long screwdriver in the plug wire end and lay the screw driver metal shaft within a half inch or so of the coil terminal. They will jump about an inch gap or so but you dont need that much to see the spark. While you hold or set the screwdriver near the coil terminal have someone else crank the car and see if you have spark. If you do have spark then its not your crank sensor. If you DONT have spark you may be in for a ride! I have seen some pretty strange crap over the years I have done drivability and electrical work on cars, and came across a really strange problem like yours in an article a few years ago. The customers car would randomly die just as yours though it was more spread out. After using a scope on the crank sensor output and ignition module output and weeks of ongoing diag work they found that a ground splice in the ignition/front engine wiring harness was bad. They replaced the harness rather than repair it as the whole thing looked bad and that took care of it. Most people dont have a scope or I would tell you to watch the crank sensor output signal. Also keep in mind that the crank sensor goes to the ignition module, then to the pcm so if the ignition module is going bad, has a bad ground it too can cause the car to die so check wiring on it. I had a car a few years ago that acted like this and it was the fuel pump. I was convinced it was the resister and drove the car for a week until I finally nailed it down. The pump would go weak and the pressure would drop to about 10psi and the car would die. You could instantly key it back up and pressure would be fine until you started the car, if it would start, then the pressure would nose right off. It was very hit and mis but once it started it kept doing it. As mentioned above dont just trust hearing the pump because that threw me off also, but the gauge didnt lie! If you had a scanner that shows crank signal that would really help out also and I dont think the atap will do that. You should be able to see rpm while cranking and running as the data stream will still communicate. I hope this gives you a few more ideas, I love this kind of stuff because I get to use the fancy tools to diag lol.
 
SyntheticShield said:
Yeah, Id be a little, well, scared to crank the engine with a wrench on it. I did buy one big honker of a breaker bar at AutoZone tonight along with the CPS sensor. Problem is now I dont know what size bolt that is on the pulley.

I have a harmonic balance puller from my last GP but it was an '89 SE and only had the 2.8L V6. Is there something special about this balancer that I would need a special puller?

How do I get that sucker back on also? Just get it started and use the bolt to pull it in as its tightened down?
Click to expand...

If you have to pull the balancer, you can use the Autozone balance puller, but you need to get (3) 1/4"-28 x 3" Grade 8 bolts and washers to hold the puller on the balancer. Also, don't let the big puller bolt go inside the balancer or it will ding the crank threads. Go to Home Depot and purchase some 3/8" rod, and cut a 2" piece off. Cover that piece with some clear tubing or 3/8" id PCV and slide that in the balancer hole first. That will protect the threads.

Some more info at Eric Buono's cam install page.
Eric Buono's Cam Install

I think the crank bolt is 24mm, but it may be a SAE size as well, so someone else will have to help you there.

Putting it on, just push it on as far as possible and use the bolt to press it on. Move the vice grips to the other side of the block and torque it down.

All of this is easier below the car, so put it on jack stands or ramps and go for it. To get to the flywheel, remove the plastic inspection cover by the starter and you should be able to get the vice grips in.

And FWIW, I have taken one off with the engine cranking method, but that was on a different car that I couldn't get vice grips on.
 
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