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Demon I Am
06-24-2013, 04:10 PM
The car died on the road Friday morning. Loss of horsepower and nonresponse from the throttle, until the engine stopped and would not crank. Towed car to work, and I can get it to crank but will either idle at 400rpm or closer to 1000. It will then slowly run down until shutoff, within 3 to 10 seconds.
Tests Performed:
Verified CAS : 12v signal and ground CMK was fluctuating, using a multimeter, so no definite reading
Verified MAF: Unplugged maf, no change in operation. CEL came on when unplugged
Verified TPS: Unplugged with no change
Checked Spark: spark on all 4 cyl, #4 cyl weaker than others, plugs with normal wear black/grey with ashy white on tip. no oil, plug tips not wet after cranking attempts, but do smell of fuel.
Cold compression test: Cyl 1 90/125/150
Cyl 2 70/90/125
Cyl 3 70/120/140
Cyl 4 70/120/140
Vacuum gauge test (Cold): within 1 sec of cranking, 22hg of vacuum. immediately drops to 13-15, the needle fluctuates rapidly between 10-15, 13-15, 17-19 on separate idling attempts. Eventually, the 17-19 became 13-15 before dying out. In all 3 attempts, needle moved very rapidly.
Exhaust:Exhaust felt like it had a decent pulse coming out of it. Have not removed and verified cat status.
Fuel pump: FP GND test, could hear pump running. Have not verified Fuel pump relay/fuel pressure/fuel volume, but car starts and idles for varying lenghts of time.
FPR: pulled the hose, and it does smell like fuel, but is not wet.
Valve Cover: pulled and visual inspection, nothing found out of place. no cracks,debris, etc.

Also, it goes through about 1.5 qt of oil per 2 weeks

Any advice or suggestions, please?

Agent☣Orange
06-24-2013, 04:14 PM
IAC?

Demon I Am
06-24-2013, 04:30 PM
trying to run the car on GND/TEN Diagnostic makes no change.

kung fu jesus
06-24-2013, 04:45 PM
Tony, has any of the wiring harness been cut for any add-on modification? I am talking about the harness coming into the ECU for say a Bipes or something. If you find any butt or crimp connectors, re-do them. I had one on mine come apart and the car didn't run well at all. I know about the CAS wiring...

Check ALL the grounds, especially the one(s) under the car?

Demon I Am
06-24-2013, 05:00 PM
The car has been unmolested, minus a radio install, that I removed and fixed. I'll start looking over grounds.

Demon I Am
06-24-2013, 05:51 PM
Coil pack: primary windings right(fires plug 1 and 4) consistent 1.2 ohms, left pack reading (fires plug 2 and 3) varies 1.2, 1.3, 2.2, 3.6. Should the writing harness be removed from the coil pack (already removed from car) when doing this?

Secondary windings: righT (fires plug 1 and 4) 12.65 kohm. Left (fires plug 2 and 3) 12.71

kung fu jesus
06-25-2013, 06:52 AM
No. You tested it right. The left is getting a little dodgy, but it doesn't explain the issue.

ya boy willz
06-25-2013, 08:44 AM
Here's a little information on vacuum gauge readings from my Automotive Engines Book.

- Cranking Vacuum should be 3 to 6 inches of Hg.
- A proper engine should hold a steady vacuum of 17-21 in Hg at idle.
- If the vacuum is less that that but steady common causes are:
~Retarded ignition timing or retarded cam timing
- If the needle keeps dropping and then returning to a normal reading this indicates a sticking valve.
- A gauge reading with the needle fluctuating 3 to 9 in. Hg below normal often indicates a vacuum leak in the intake system.
- A leaking head gasket can cause the needle to vibrate as it moves through a range from below to above normal.
- An oscillating needle 1 or 2 in. HG below normal could indicate incorrect air fuel mixture.
- Weak valve springs will produce a normal reading at idle, but as engine speed increases the needle will fluctuate between 12 and 24 in. Hg.
- A rapidly vibrating needle at idle that becomes steady as engine speed increases indicates worn valve guides.
- If the needle drops 1 or 2 in. Hg from the normal reading an engine valve is burned or not seating properly.
- A needle that drops to near zero when the engine is accelerated rapidly and then rises slightly to a reading below normal indicates an exhaust restriction.

If I understand your situation correctly I might try checking for an intake leak or clogged cat. And if you can, try to do a cylinder leakage test. As your cyl 2 compression being a little low plus it burning a decent amount of oil might mean that one of your valves is starting to go/is burned up.

Demon I Am
06-25-2013, 09:00 AM
lots of stuff pointing to the cat. I will remove that tonight and try to run it open header. also need to check the fuel pump relay

tsingson
06-25-2013, 09:09 AM
I thought you were running a straight pipe?

Demon I Am
06-25-2013, 09:23 AM
oh hell no! never again. The 1.6 had a test pipe, and stock muffler.

Phatmiata
06-25-2013, 09:29 AM
If it's a stock cat when they fall apart they will clog up the exhaust and the car won't run worth a damn, so that could be very possible. That same thing happened on my 1.6L, but then they are 20 year old cars.

tsingson
06-25-2013, 10:37 AM
You could always bash the cat out if it is indeed clogged.

Demon I Am
06-27-2013, 02:47 PM
unbolted cat and moved it aside, no change in (lack of) performance.
looked at all of the under-hood wiring, no loose/broken/corroded grounds.
took entire intake track apart, no clogs.
Checked all vacuum lines and caps. All good.

>:(

Demon I Am
06-27-2013, 08:17 PM
Problem solved.
Fuel pump was shot. I tried the starter fluid trick, which was successful in keeping the car running. Tested the wiring, and it was all good at the fuel pump, so I decided to replaced it. Put it together, primed the system, and she was good to go. Replaced the sock, which I had to buy seperately for some dumb reason. Also bought a fuel filter, but that can wait until I have daylight again.

WDBMX5
06-27-2013, 08:35 PM
glad u got it fixed...i know u r happy now

Demon I Am
06-27-2013, 11:25 PM
yeah, but in the process, I may have funked the starter. A few times I have noticed it taking longer to crank, and it is less than 1 year old

JLBMX5
06-28-2013, 04:34 AM
If it is a chain store auto parts starter they usually come with a lifetime warranty. But if it kicks over at all while they test it sometimes they will say its good and make you use it till its 100% dead.