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-   -   Crank and start, crank and shut down(3 sec) crank and no start (http://986forum.com/forums/showthread.php?t=64977)

Camibox 01-13-2017 01:34 PM

Crank and start, crank and shut down(3 sec) crank and no start
 
Same symptoms over the last few attempts. Cranks and runs fine 5 to 10 min then we shut it down. try to start a few seconds later and it starts and dies about 3 seconds later. Third attempt is then crank but no start. No CEL codes. fuel tank at 1/2. I have replaced the fuel pump relay. When I jumper the relay I can hear the pump running. This same sequence happened 3-4 times already with a 10-30 minute wait between each test.
Help Please

Gelbster 01-13-2017 01:41 PM

Give us ALL the details - what have you done to it recently? Codes ,CEL ? Black smoke/white smoke ?
What fuel pressure test did you do?
How many miles?
Old gelled gas? Old - more than 3 months in the tank !
Tested the fuel pressure regulator
Old ,plugged fuel filter ?

Camibox 01-13-2017 01:48 PM

What fuel pressure test did you do? Haven't done one. Will look up how
How many miles? 160K
Old gelled gas? Old - more than 3 months in the tank ! Good gas
Tested the fuel pressure regulator Same as above
Old ,plugged fuel filter ? Changing it this afternoon

Thanks

Camibox 01-13-2017 01:51 PM

It's a 99, manual, good battery

Gelbster 01-13-2017 02:08 PM

Quote:

Originally Posted by Camibox (Post 522571)
What fuel pressure test did you do? Haven't done one. Will look up how
How many miles? 160K
Old gelled gas? Old - more than 3 months in the tank ! Good gas
Tested the fuel pressure regulator Same as above
Old ,plugged fuel filter ? Changing it this afternoon

Thanks

Pelican has good diy on changing the fuel filter. Horrid job ! Careful with the hose clips You really need to use special hose clamp pliers .
160k miles ! wow, you may have a long li$t of deferred maintenance ?

WorkInProgressK 01-13-2017 03:50 PM

Does the symptoms persist with the fuel pump relay by passed? Forcing the fuel pump to run at 100% all the time direct from the battery. This sounds like a weak fuel pump needing more amps to run or clogged fuel filter(most have bypasses, so it be hard to diagnose). Modern cars tend to send a little less power to the pump to make them waste less energy. From experience, my 240sx's from the 90s, would limit current to the pump at partial throttle. Now with forced induction you need more fuel at that partial throttle so it would lean out. I rewired it direct, bypassing the original relay.

In your case it's just to make sure its fuel related. Then keep up with the maintenance and if it does it again, maybe the fuel pump needs replacing. High flowing pumps tend to be cheaper alternatives. Something like walbro255 could do the trick and be cheaper then stock.

Qmulus 01-14-2017 09:01 AM

Sounds like a crank position sensor to me...

Gelbster 01-14-2017 09:28 AM

CPS ?? but it does not seem to fail when hot.It fails within a few minutes of starting.
Easy diagnosis - rev counter needle bounce test
at 160k miles it is kinda due for everything?

Mark_T 01-14-2017 10:56 AM

I had a condition where the car would start and immediately die. Turned out to be the MAF. Have you tried unplugging the MAF to see if the makes a difference?

78F350 01-14-2017 11:17 AM

Quote:

Originally Posted by Qmulus (Post 522669)
Sounds like a crank position sensor to me...

+1
When I read the 1st post it immediately reminded me of 3 other cars I've fixed that had similar symptoms.

Camibox 01-14-2017 11:30 AM

Update: Last night I replaced the fuel filter and did an oil change when I was under there. This morning after a few seconds cranking it fired right up. We let it run about 5 minutes and it started to die. Shut it down and fired up again. Started and barely idled, she had her foot to the floor and barely idle speed and rough. To me sounded fuel starved. CPS and Fuel pump? Thanks

Gelbster 01-14-2017 12:20 PM

CPS test
JFP recently posted test values for the CPS .SOmeone may be able to link that post?
This may help:
lets discuss Crank Position Sensors for a moment - Rennlist Discussion Forums

Lapister 01-14-2017 03:17 PM

Do you have a shcrader valve on the fuel rail to check at minimum your pressure? You can eliminate fuel problem that way. Then move on?

ccjazz 01-14-2017 03:46 PM

JFP comments on CPS...post#6 in this thread.

http://986forum.com/forums/general-discussions/64861-cranks-shaft-position-sensor-wiring-schematic-ohm-readings.html

I have also read that the tach needle should bounce off of '0' when cranking the engine. If it doesn't it could show a malfunctioning CPS.

BFeller 01-14-2017 07:45 PM

When my CPS died the car had no history of issues. I pulled the car out of the garage. A few hours later went to move it back - it never started until the CPS was replaced. So do not really on it not being CPS because it did not fail when hot.

Gelbster 01-14-2017 08:16 PM

Long before the CPS fails the measured resistance may be out of spec. Hence the prior recommendation and link with specs to test it. All you need is a free Harbor Freight multimeter.

Camibox 02-07-2017 06:26 PM

Update: So I replaced the CPS. I didn't test the new one before I replaced it but tested the old and had no continuity between any of the pins (all read OL). Went to start the car and cranked but didn't try to catch. Saw the tach rise slightly but realized I never heard the fuel pump. Pulled the relay and put in a switch to test. Fuel pump activated. tried the car and it fired right up. 4 times and fired up every time. Wife says "Huh, bad relay". One of the first thing I did was replace the relay but it couldn't hurt, right. Replaced the relay and 3-4 more tries, no issue. We'll see how it goes when we try again tomorrow. BTW, I did test the relay I removed and it activated when I put voltage to the coil.

Gelbster 02-07-2017 07:17 PM

Fuel Pump relay - What brand/part # and spec did you use/replace?
996-615-101-00 fits mine.
I ask because some of the $2.00 relays that claim to be Interchangable are doubtful.
Meanwhile - keep that jumper lead you made handy !
As soon as you stop the car after running for 20 minutes+ ,feel ith fuel pump relay - is it hot to the touch?

Camibox 02-08-2017 12:01 PM

Same relay number (KAE) I tested a few more times and got a few where it didnt activate. The 87 pin is loose which may have been an issue. Will get the top on and have her test it out. Now about the leak I saw at the water pump.......

Gelbster 02-08-2017 12:12 PM

Quote:

Originally Posted by Camibox (Post 526217)
The 87 pin is loose which may have been an issue. ...

That would do it ! Good diagnosis for others to follow - wiggle the pins ! If you can do this with an Multi Meter set to 200 ohms and attached to the coil pins it may be conclusive.
You mentioned W/p - look for water/mineral stains on the pump -just under the shaft. If there are none ,look elsewhere for leakage.
Consider upgrading to the low temp T-stat (Wahler)at the same time .Pelican have it.


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