Need help! Cranks but doesn't start.
Thread Starter
Pro
Joined: Oct 2012
Posts: 611
Likes: 30
From: Tampa Bay, FL
Need help! Cranks but doesn't start.
Greetings! As the titles states, my 96C2 w/103K will not start; it cranks but nothing more.
Background: over the last year, I started experiencing hot start issues where, after a drive and short stop, the car would not start right away. In trying to start it, I would hear a high wind noise (starter pinion spinning but not engaging?). After trying again once or twice and giving it some throttle input, it would start. As of recent, it just cranks but nothing else.
As I continue to troubleshoot, I've performed some related and unrelated maintenance in the hope that I'll find the culprit:
- 2yo battery tested - holds steady at 12.61v
- DME relay swapped with new
- DME relay successfully bypassed with jumper
- Fuel pump fuse checked and good
- New fuel filter
- ISV cleaned
- SAI clean-out
- MAF cleaned
- New spark plugs
- New distributor caps and rotors
- New crank position sensor
In reading numerous posts and threads, some of the recommendations were to check/replace:
- fuel pressure regulator,
- head temp sensor,
- (of course) the actual starter.
Thoughts on cause and way forward. What am I missing?
Thanks in advance!
Background: over the last year, I started experiencing hot start issues where, after a drive and short stop, the car would not start right away. In trying to start it, I would hear a high wind noise (starter pinion spinning but not engaging?). After trying again once or twice and giving it some throttle input, it would start. As of recent, it just cranks but nothing else.
As I continue to troubleshoot, I've performed some related and unrelated maintenance in the hope that I'll find the culprit:
- 2yo battery tested - holds steady at 12.61v
- DME relay swapped with new
- DME relay successfully bypassed with jumper
- Fuel pump fuse checked and good
- New fuel filter
- ISV cleaned
- SAI clean-out
- MAF cleaned
- New spark plugs
- New distributor caps and rotors
- New crank position sensor
In reading numerous posts and threads, some of the recommendations were to check/replace:
- fuel pressure regulator,
- head temp sensor,
- (of course) the actual starter.
Thoughts on cause and way forward. What am I missing?
Thanks in advance!
Race Car
Joined: May 2003
Posts: 4,241
Likes: 103
From: SoCal
Greetings! As the titles states, my 96C2 w/103K will not start; it cranks but nothing more.
Background: over the last year, I started experiencing hot start issues where, after a drive and short stop, the car would not start right away. In trying to start it, I would hear a high wind noise (starter pinion spinning but not engaging?). After trying again once or twice and giving it some throttle input, it would start. As of recent, it just cranks but nothing else.
As I continue to troubleshoot, I've performed some related and unrelated maintenance in the hope that I'll find the culprit:
- 2yo battery tested - holds steady at 12.61v
- DME relay swapped with new
- DME relay successfully bypassed with jumper
- Fuel pump fuse checked and good
- New fuel filter
- ISV cleaned
- SAI clean-out
- MAF cleaned
- New spark plugs
- New distributor caps and rotors
- New crank position sensor
In reading numerous posts and threads, some of the recommendations were to check/replace:
- fuel pressure regulator,
- head temp sensor,
- (of course) the actual starter.
Thoughts on cause and way forward. What am I missing?
Thanks in advance!
Background: over the last year, I started experiencing hot start issues where, after a drive and short stop, the car would not start right away. In trying to start it, I would hear a high wind noise (starter pinion spinning but not engaging?). After trying again once or twice and giving it some throttle input, it would start. As of recent, it just cranks but nothing else.
As I continue to troubleshoot, I've performed some related and unrelated maintenance in the hope that I'll find the culprit:
- 2yo battery tested - holds steady at 12.61v
- DME relay swapped with new
- DME relay successfully bypassed with jumper
- Fuel pump fuse checked and good
- New fuel filter
- ISV cleaned
- SAI clean-out
- MAF cleaned
- New spark plugs
- New distributor caps and rotors
- New crank position sensor
In reading numerous posts and threads, some of the recommendations were to check/replace:
- fuel pressure regulator,
- head temp sensor,
- (of course) the actual starter.
Thoughts on cause and way forward. What am I missing?
Thanks in advance!
Thread Starter
Pro
Joined: Oct 2012
Posts: 611
Likes: 30
From: Tampa Bay, FL
Thx for the reminder, Tore! Yes, this is also on my to-do list. Should I check at the end of the spark plug wire, at the distributor, or both?
Race Car
Joined: May 2003
Posts: 4,241
Likes: 103
From: SoCal
RL Community Team
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From: Dallas, TX
Have you run OBDC codes with the ignition on and the ignition immobilizer not active you should be able to read the codes?
If you can't access the Motronic ECU you may have an immobilizer issue.
Not sure if bypassing the fuel pump relay eliminates the immobilizer as a non-start root cause for testing purposes but someone here can probably answer that question.
Andy
If you can't access the Motronic ECU you may have an immobilizer issue.
Not sure if bypassing the fuel pump relay eliminates the immobilizer as a non-start root cause for testing purposes but someone here can probably answer that question.
Andy
Thread Starter
Pro
Joined: Oct 2012
Posts: 611
Likes: 30
From: Tampa Bay, FL
Have you run OBDC codes with the ignition on and the ignition immobilizer not active you should be able to read the codes?
If you can't access the Motronic ECU you may have an immobilizer issue.
Not sure if bypassing the fuel pump relay eliminates the immobilizer as a non-start root cause for testing purposes but someone here can probably answer that question.
Andy
If you can't access the Motronic ECU you may have an immobilizer issue.
Not sure if bypassing the fuel pump relay eliminates the immobilizer as a non-start root cause for testing purposes but someone here can probably answer that question.
Andy
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Race Car
Joined: May 2003
Posts: 4,241
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From: SoCal
Have you done the simplest test (15 seconds of effort), i.e. pull the coil wire from one distributor and place (15mm) near engine metal and have someone crank the engine?
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RL Community Team
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From: Dallas, TX
Think about global issues first, Fuel supply, Presence of high voltage, etc. You can waste a lot of time and money going down the individual cylinder is the issue approach. When you first turnthe ignition on do you hear the fuel pump cycle for a moment verifying that it is working?
Andy
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Joined: Jul 2004
Posts: 5,022
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From: Berkeley Lake, Georgia
Ignition coils may be deteriorated as mentioned in above posts based on stuff you already checked........let us know what happens.....thanks in advance and hope u find the culprit soon!
Drifting
Joined: Nov 2008
Posts: 2,340
Likes: 79
From: Vancouver BC, Canada
I had somewhat a similar issue many years back that was triggered when I sent my injectors to get cleaned as part of spark plug maintenance service. The shop damaged them and it was a nightmare to track down the starting issues at the time since I went thru everything related to the fuel system. In the end came back to the injectors.
Mine actually had issues with a cold start or say after 2 hours sitting. Hot start would be fine but still very rough.
So my suggestion check the:
head temp sensor (easily done I recall)
injectors
fuel pressure regulator
Good luck!
Mine actually had issues with a cold start or say after 2 hours sitting. Hot start would be fine but still very rough.
So my suggestion check the:
head temp sensor (easily done I recall)
injectors
fuel pressure regulator
Good luck!
Thread Starter
Pro
Joined: Oct 2012
Posts: 611
Likes: 30
From: Tampa Bay, FL
Update 1:
Since the last post I've replaced the fuel pressure regulator with no luck. So, based on my previous checks, and if i understand it correctly, the fuel system is fully working.
Now I tested the ignition coils. Primary circuit showed 0 resistance on both coils, secondary circuit showed 8.68k and 8.85k. If I am to understand this correctly, my ignition coils are toast. Am I correct to assume this?
Thx!
Bruno
Since the last post I've replaced the fuel pressure regulator with no luck. So, based on my previous checks, and if i understand it correctly, the fuel system is fully working.
Now I tested the ignition coils. Primary circuit showed 0 resistance on both coils, secondary circuit showed 8.68k and 8.85k. If I am to understand this correctly, my ignition coils are toast. Am I correct to assume this?
Thx!
Bruno
RL Community Team
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From: Dallas, TX
Update 1:
Since the last post I've replaced the fuel pressure regulator with no luck. So, based on my previous checks, and if i understand it correctly, the fuel system is fully working.
Now I tested the ignition coils. Primary circuit showed 0 resistance on both coils, secondary circuit showed 8.68k and 8.85k. If I am to understand this correctly, my ignition coils are toast. Am I correct to assume this?
Thx!
Bruno
Since the last post I've replaced the fuel pressure regulator with no luck. So, based on my previous checks, and if i understand it correctly, the fuel system is fully working.
Now I tested the ignition coils. Primary circuit showed 0 resistance on both coils, secondary circuit showed 8.68k and 8.85k. If I am to understand this correctly, my ignition coils are toast. Am I correct to assume this?
Thx!
Bruno
"Most ignition coils should have a primary resistance falling somewhere between 0.4 and 2 ohms;"
"Most ignition coils should have a secondary resistance falling somewhere between 6,000 to 10,000 ohms; however, refer to manufacturer specifications for the correct range. If a reading of zero is displayed, that signifies that the coil has short-circuited and needs to be replaced, while an excessive reading signifies that the coil is open, and also needs to be replaced."
Drifting
Joined: Jul 2012
Posts: 2,182
Likes: 339
From: Santa Cruz, CA
Hard to believe 2 coils failed in the same way at the same time
you need a quality meter to measure sub 1 ohm
it maybe that anything less than 1ohm reads as zero
(edit) did you do Lorens simple test in post 8?
just throwing parts at the problem is a waste of time and cash
you need a quality meter to measure sub 1 ohm
it maybe that anything less than 1ohm reads as zero
(edit) did you do Lorens simple test in post 8?
just throwing parts at the problem is a waste of time and cash
Thread Starter
Pro
Joined: Oct 2012
Posts: 611
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From: Tampa Bay, FL
I read the exact same page.
https://www.yourmechanic.com/article...eduardo-ruelas
I lowered the setting on my multimeter and, lo and behold, I'm getting 0.8 ohms of resistance on both primary circuits. Combined with the results of the secondary circuit readings, and if the resistance values mentioned on the website are correct, the coil is within parameters.
https://www.yourmechanic.com/article...eduardo-ruelas
I lowered the setting on my multimeter and, lo and behold, I'm getting 0.8 ohms of resistance on both primary circuits. Combined with the results of the secondary circuit readings, and if the resistance values mentioned on the website are correct, the coil is within parameters.