Engine lost power and can't restart
05-09-2017, 12:04 PM
#1
Engine lost power and can't restart
Hello all. I am hoping to get some help in the right direction to find out what's exactly wrong in order for me to make the correct repairs.
Car is a 02 z06, just went over 50k miles. Has k&n intake and the rest is stock with the motor.
I was WOT in 4th gear at around 5200rpm, i felt a slight buck(like a fuel cut/boost cut) and I let off the throttle. Slowed down into turn one and the power kept on dropping. The car lost power and did not start again.
It threw 3 codes from the pcm after this happened.
p0101
p1514
p0343
I was at the track when this happened, 4-5 hours away from home. So, for what it was worth, I cleaned the MAF sensor and put it back on with no luck. It wasn't dirty at all.
The next day, I was able to purchase a new cmp sensor and replaced it. Again, no luck. I was lucky to run into another corvette owner, only to find out at the end he is on the forum, and he helped me determine that I have spark. The plug pulled from cyl. 1 was dry. Tested for fuel pressure by pressing on the schrader valve and fuel leaked out. I bought a fuel pressure gauge and going to test the actual fuel pressure today.
Before the the engine died, I had two codes pop up in the previous session.
c1293(does it at least once at the track, so i just pit in and restart the car)
p1575, never had this pop on before.
There was no bang, explosion, or smoke when it happened. At least the engine oil level is still good.
From what I've read online so far, i may have a snapped timing chain or it may have skipped a tooth. I don't think my cam bolts backed out, as I read a few people with cam upgrades had those issues and i haven't thouched that.
If my suspicions are correct, is there a way to diagnose the timing chain without taking everything apart? Or is there another thing that could've caused this issue?
Rob, if you're reading this post, I wanted to thank you again for your help at the track. I feel lucky to have ran into you there. I will see you soon at the track again.
Car is a 02 z06, just went over 50k miles. Has k&n intake and the rest is stock with the motor.
I was WOT in 4th gear at around 5200rpm, i felt a slight buck(like a fuel cut/boost cut) and I let off the throttle. Slowed down into turn one and the power kept on dropping. The car lost power and did not start again.
It threw 3 codes from the pcm after this happened.
p0101
p1514
p0343
I was at the track when this happened, 4-5 hours away from home. So, for what it was worth, I cleaned the MAF sensor and put it back on with no luck. It wasn't dirty at all.
The next day, I was able to purchase a new cmp sensor and replaced it. Again, no luck. I was lucky to run into another corvette owner, only to find out at the end he is on the forum, and he helped me determine that I have spark. The plug pulled from cyl. 1 was dry. Tested for fuel pressure by pressing on the schrader valve and fuel leaked out. I bought a fuel pressure gauge and going to test the actual fuel pressure today.
Before the the engine died, I had two codes pop up in the previous session.
c1293(does it at least once at the track, so i just pit in and restart the car)
p1575, never had this pop on before.
There was no bang, explosion, or smoke when it happened. At least the engine oil level is still good.
From what I've read online so far, i may have a snapped timing chain or it may have skipped a tooth. I don't think my cam bolts backed out, as I read a few people with cam upgrades had those issues and i haven't thouched that.
If my suspicions are correct, is there a way to diagnose the timing chain without taking everything apart? Or is there another thing that could've caused this issue?
Rob, if you're reading this post, I wanted to thank you again for your help at the track. I feel lucky to have ran into you there. I will see you soon at the track again.
05-09-2017, 02:12 PM
#2
Instructor
Sounds like you really need to focus on Fuel and Spark delivery before you start randomly tearing into things.
But you can always pull a valve cover and spin the engine to watch all the little rockers mover up and down.
What is your fuel pressure reading would be the first question to answer.
But you can always pull a valve cover and spin the engine to watch all the little rockers mover up and down.
What is your fuel pressure reading would be the first question to answer.
05-09-2017, 02:24 PM
#3
Instructor
Does the throttle plate still actuate?
With the ignition in the on position, but the engine not running press the throttle petal down and either have somebody watch or use you obd2 box to read TPS. Verify the throttle plate opens.
P0101 + P1514 sounds like the electronic throttle is not working.
P0343 has a history of sensor failure, more likely than mechanical failure anyways.
With the ignition in the on position, but the engine not running press the throttle petal down and either have somebody watch or use you obd2 box to read TPS. Verify the throttle plate opens.
P0101 + P1514 sounds like the electronic throttle is not working.
P0343 has a history of sensor failure, more likely than mechanical failure anyways.
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DK83 (05-09-2017)
05-09-2017, 03:03 PM
#4
I pulled the spark plug from cylinder #1 at the track and that had spark. I had a fellow vette owner check the spark while I cranked the engine. Should I check the spark on all of the spark plugs?
Just did a fuel pressure test and it read 62psi~ish while I was cranking the engine. Is this a good pressure?
I also hear random pops as I'm trying to start the key. It doesn't happen all the time, but it does happen. Again, I already replaced the cam position sensor to no avail.
I'm going to hook up my obd2 reader and see about the tps
Just did a fuel pressure test and it read 62psi~ish while I was cranking the engine. Is this a good pressure?
I also hear random pops as I'm trying to start the key. It doesn't happen all the time, but it does happen. Again, I already replaced the cam position sensor to no avail.
I'm going to hook up my obd2 reader and see about the tps
Does the throttle plate still actuate?
With the ignition in the on position, but the engine not running press the throttle petal down and either have somebody watch or use you obd2 box to read TPS. Verify the throttle plate opens.
P0101 + P1514 sounds like the electronic throttle is not working.
P0343 has a history of sensor failure, more likely than mechanical failure anyways.
With the ignition in the on position, but the engine not running press the throttle petal down and either have somebody watch or use you obd2 box to read TPS. Verify the throttle plate opens.
P0101 + P1514 sounds like the electronic throttle is not working.
P0343 has a history of sensor failure, more likely than mechanical failure anyways.
Last edited by DK83; 05-09-2017 at 03:03 PM.
05-09-2017, 04:35 PM
#6
Drifting
Do you have a compression tester? If you have fuel and spark, the only thing really left is compression. The compression will be low if the chain jumped a tooth. If the chain broke, you would probably hear some nasty noises as the chain would be hitting something. The engine will run fine without a cam position sensor, it just won't start half the time. I ran without one for probably two seasons.
05-09-2017, 04:38 PM
#7
Sounds like it's not getting fuel. These are cheap and worth tossing into your "track" tool box
OTC Noid light...just plugs into fuel injector harness and gives you a one man visual indication if the injector is firing. Sounds like you have fuel pressure. You should be able to hear the pump run when you first key on the ignition.
OTC Noid light...just plugs into fuel injector harness and gives you a one man visual indication if the injector is firing. Sounds like you have fuel pressure. You should be able to hear the pump run when you first key on the ignition.
Last edited by SocalC5Z; 05-09-2017 at 04:39 PM.
05-09-2017, 04:42 PM
#8
Instructor
I pulled the spark plug from cylinder #1 at the track and that had spark. I had a fellow vette owner check the spark while I cranked the engine. Should I check the spark on all of the spark plugs?
Just did a fuel pressure test and it read 62psi~ish while I was cranking the engine. Is this a good pressure?
I also hear random pops as I'm trying to start the key. It doesn't happen all the time, but it does happen. Again, I already replaced the cam position sensor to no avail.
I'm going to hook up my obd2 reader and see about the tps
Just checked the throttle plate and it opens up all the way.
Just did a fuel pressure test and it read 62psi~ish while I was cranking the engine. Is this a good pressure?
I also hear random pops as I'm trying to start the key. It doesn't happen all the time, but it does happen. Again, I already replaced the cam position sensor to no avail.
I'm going to hook up my obd2 reader and see about the tps
Just checked the throttle plate and it opens up all the way.
If the timing chain snapped there would be valvetrain interfence and bent valves and general mayhem.
What if the chain slipped a tooth? Would be hard to diagnose. Best way without having to pull the front cover would be to degree the cam.
Pull a valve cover and use dial indicator and see if specs match up.
Engines generally run, but poorly, with the cam off by a tooth.
You could also check compression, would be universally low with mis timed cam.
What about the reluctor wheel? Those can occasionally slip also.
With the general lack of drama in the failure, spark and fuel seems most likely, so maybe a timing check?
Turn over the enigine with a timing light and see if it sparks near TDC?
Back to the MAF, maybe its gone totally none linear, just disconnect it and see if car runs?
05-09-2017, 07:21 PM
#9
Melting Slicks
Pro Mechanic
Member Since: Nov 2013
Location: Ex DPRK, now just N of Medford, OR
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You can do a quick check of the cam timing to see if it's in the ballpark:
Watch the rockers for #1 cylinder... turn the engine in normal direction, watch for exhaust to open and then start to close, as it's closing, the intake will start to open. When they're both open about the same amount, timing marks should be approx TDC.
If they never open... bummer.
Rule of thumb: "look for split valve overlap at exhaust TDC". Served me well over many years...
Watch the rockers for #1 cylinder... turn the engine in normal direction, watch for exhaust to open and then start to close, as it's closing, the intake will start to open. When they're both open about the same amount, timing marks should be approx TDC.
If they never open... bummer.
Rule of thumb: "look for split valve overlap at exhaust TDC". Served me well over many years...
Last edited by Nowanker; 05-09-2017 at 07:22 PM.
05-09-2017, 08:53 PM
#10
Tech Contributor
Member Since: Oct 1999
Location: Charlotte, NC (formerly Endicott, NY)
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There was a TSB related to P0101 and it might be worth checking into.
#PI01624A: Service VME - 4.8 5.3 6.0 LM4 LM7 LR4 LQ4 LQ9 GEN III Engines with MAF Sensor Code P0101 - kw driveability fluctuation idle intermittent MAP rough stall surge hesitation - (Apr 5, 2004)
Subject: Service VME - 4.8 5.3 6.0 LM4 LM7 LR4 LQ4 LQ9 GEN III Engines with MAF Sensor Code P0101
Models: .
When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.
SERVICE VME
This message applies to all 1999 through 2004 Chevrolet, GMC, Olds, Buick and Cadillac pick-ups and utilities that are equipped with either the 4.8 liter, 5.3 liter or 6.0 liter Gen 3 V-8 engines. Recent warranty analysis indicates that both the MAF, or mass airflow sensor, and the MAP, or manifold absolute pressure sensor, are being replaced for a MAF sensor code P0101. The cause may actually be a MAP sensor failure causing the MAF sensor code. One of the MAP sensor’s primary functions is the calculation of the speed density formula, which is compared to the MAF sensor reading. Should the MAP sensor fail, the PCM may interpret this as a MAF sensor concern and set a P0101 code. If diagnostics are followed thoroughly the technician may find a MAP sensor failure causing this condition. In conclusion, when a MAF sensor code of P0101 is found the technician needs to verify the proper operation of the MAP sensor before concluding that the MAF sensor requires replacement.
.
Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.
.
MODELS:
(00-04 Chevrolet Silverado Truck C1,C2,C3) and (00-04 Chevrolet Tahoe C1,C2,C3) and (00-04 Chevrolet Suburban C1,C2,C3) and (00-04 GMC Sierra Truck C1,C2,C3) and (00-04 GMC Yukon C1, C2, C3) and (00-04 GMC Yukon XL C1, C2 C3) and (02-04 Cadillac, Escalade, C6) and (03-04 Cadillac, EXT, C1) and (02-043 Chevrolet, Avalanche, K1, K2) and (02-04 Chevrolet Silverado Truck K1, K2, K3) and (02-04 GMC Sierra Truck K1, K2, K3) and (02-04 Chevrolet Tahoe, K1, K2, K3) and (02- 04 Chevrolet Suburban, K1, K2, K3) and (03 Chevrolet Camaro) and (02-04 Chevrolet Corvette) and (03 Pontiac Firebird) and (02-04 GMC, Yukon, K1, K2, K3) and (02-04 GMC, Yukon XL, C1,C2, C3) and (00-04 GMC, Yukon XL, K1, K2, K3) and (03-04 GMC S1 T1) and (03-04 Chevrolet S1 T1) and (03-04 Chevrolet Express G1, G2) and (03-04 GMC Savana G1, G2)
I am attaching a PDF with diagnostic procedures from the FSM that relate to the codes you have seen. The problem mentioned in the TSB could probably generate a bunch of issues other than the brake one.
Bill
#PI01624A: Service VME - 4.8 5.3 6.0 LM4 LM7 LR4 LQ4 LQ9 GEN III Engines with MAF Sensor Code P0101 - kw driveability fluctuation idle intermittent MAP rough stall surge hesitation - (Apr 5, 2004)
Subject: Service VME - 4.8 5.3 6.0 LM4 LM7 LR4 LQ4 LQ9 GEN III Engines with MAF Sensor Code P0101
Models: .
When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.
SERVICE VME
This message applies to all 1999 through 2004 Chevrolet, GMC, Olds, Buick and Cadillac pick-ups and utilities that are equipped with either the 4.8 liter, 5.3 liter or 6.0 liter Gen 3 V-8 engines. Recent warranty analysis indicates that both the MAF, or mass airflow sensor, and the MAP, or manifold absolute pressure sensor, are being replaced for a MAF sensor code P0101. The cause may actually be a MAP sensor failure causing the MAF sensor code. One of the MAP sensor’s primary functions is the calculation of the speed density formula, which is compared to the MAF sensor reading. Should the MAP sensor fail, the PCM may interpret this as a MAF sensor concern and set a P0101 code. If diagnostics are followed thoroughly the technician may find a MAP sensor failure causing this condition. In conclusion, when a MAF sensor code of P0101 is found the technician needs to verify the proper operation of the MAP sensor before concluding that the MAF sensor requires replacement.
.
Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.
.
MODELS:
(00-04 Chevrolet Silverado Truck C1,C2,C3) and (00-04 Chevrolet Tahoe C1,C2,C3) and (00-04 Chevrolet Suburban C1,C2,C3) and (00-04 GMC Sierra Truck C1,C2,C3) and (00-04 GMC Yukon C1, C2, C3) and (00-04 GMC Yukon XL C1, C2 C3) and (02-04 Cadillac, Escalade, C6) and (03-04 Cadillac, EXT, C1) and (02-043 Chevrolet, Avalanche, K1, K2) and (02-04 Chevrolet Silverado Truck K1, K2, K3) and (02-04 GMC Sierra Truck K1, K2, K3) and (02-04 Chevrolet Tahoe, K1, K2, K3) and (02- 04 Chevrolet Suburban, K1, K2, K3) and (03 Chevrolet Camaro) and (02-04 Chevrolet Corvette) and (03 Pontiac Firebird) and (02-04 GMC, Yukon, K1, K2, K3) and (02-04 GMC, Yukon XL, C1,C2, C3) and (00-04 GMC, Yukon XL, K1, K2, K3) and (03-04 GMC S1 T1) and (03-04 Chevrolet S1 T1) and (03-04 Chevrolet Express G1, G2) and (03-04 GMC Savana G1, G2)
I am attaching a PDF with diagnostic procedures from the FSM that relate to the codes you have seen. The problem mentioned in the TSB could probably generate a bunch of issues other than the brake one.
Bill
05-09-2017, 09:18 PM
#11
I didn't read all of that, but if you don't have spark, check the ground wire behind the driver's side head. It's a booger, but if the small wire breaks, you won't have engine ground or fire on a c5 vette.
05-13-2017, 09:26 PM
#12
Update.
i took the timing chain cover off and the chain was snapped. I guess time for upgrades starting with the chain.
edit:
Been doing a bunch of reading and searching the past few days. I still haven't taken the head off yet, so further inspection of pistons and valves will be done soon.
Starting with what I know now, what's the best replacement for the timing chain?
I've read about the ls2, c5r, the cloyes, and double rollers. I see conflicting information regarding single vs double rollers. What about the cam and crank sprockets? Get OEM replacements or are there upgrade options?
I need to confirm if my car has holes for the dampener, which one is best?
Car is 70% track 30% street car and I intend to keep it that way. With the chain being snapped off I'm going to make some upgrades.
Currently car is stock with just a k&n intake. As of today, I am certain that I will upgrade the cam and headers. I'm still researching on the camshaft, but have learned that no more than .580 lift. I'm leaning towards arh 1 3/4 headers at this point.
My primary goal is reliability and low maintanance. Then, smooth/useable power delivery at the track.
i took the timing chain cover off and the chain was snapped. I guess time for upgrades starting with the chain.
edit:
Been doing a bunch of reading and searching the past few days. I still haven't taken the head off yet, so further inspection of pistons and valves will be done soon.
Starting with what I know now, what's the best replacement for the timing chain?
I've read about the ls2, c5r, the cloyes, and double rollers. I see conflicting information regarding single vs double rollers. What about the cam and crank sprockets? Get OEM replacements or are there upgrade options?
I need to confirm if my car has holes for the dampener, which one is best?
Car is 70% track 30% street car and I intend to keep it that way. With the chain being snapped off I'm going to make some upgrades.
Currently car is stock with just a k&n intake. As of today, I am certain that I will upgrade the cam and headers. I'm still researching on the camshaft, but have learned that no more than .580 lift. I'm leaning towards arh 1 3/4 headers at this point.
My primary goal is reliability and low maintanance. Then, smooth/useable power delivery at the track.
Last edited by DK83; 05-13-2017 at 10:19 PM.