fullymatted.
Back to search
Rennlist

Intermittent crank-no start; is this CPS

Add to repair workspace
Open repair workspace
Original source
2 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHIntermittent crank-no start; is this CPS

Reported or suspected cause

crankshaft position sensor

Suggestion or failed attempt

No successful repair reported for this finding.

0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that suspect a cause
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suspected cause

If not, it's likely a bad crankshaft position sensor.

Original post Read captured discussion
Intermittent crank-no start; is this CPS
Frequently discussed work

Replace cps

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Is there anything else I can/should do to check this prior to replacing the CPS?

Original post Read captured discussion
Intermittent crank-no start; is this CPS
Read full discussion summary

Leading evidence: 'crankshaft position sensor' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'crankshaft position sensor' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Replace cps' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

Read captured replies

1 matching discussions · 2 captured posts examined · 0 partial discussions

Compare 1 other evidence results

Replace cps

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Is there anything else I can/should do to check this prior to replacing the CPS?

Original post Read captured discussion
Intermittent crank-no start; is this CPS
Frequently discussed actions (1)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Replace cps

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

Is there anything else I can/should do to check this prior to replacing the CPS?

Original post Read captured discussion
Intermittent crank-no start; is this CPS
Reported and suspected causes (1)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

crankshaft position sensor

No successful repair reported for this finding.

0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that suspect a cause
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suspected cause

If not, it's likely a bad crankshaft position sensor.

Original post Read captured discussion
Intermittent crank-no start; is this CPS
Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

2 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • Rennlist: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

1 acknowledgements have no verified action link; they do not establish a repair result.

Outcome without a verified action link

I bypassed the fuel pump relay but no change.

Original post Read captured discussion

No unique explicit quoted action; no causal link assigned

Generation: 20261027T005001Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hi there, I have an intermittent cranks fine but no start that seems to occur only when the car is warm. After I come back a few hours later the car starts again without issue. I have tried to turn off the car and restart when warm; sometimes it is successful, and sometimes I can do this more than once successively; but as soon as it does not start once subsequently it seems that it is done and I have to wait until it�s cold for it to be willing to restart. As I said, it cranks fine. I bypassed the fuel pump relay but no change. The fuel pump sounds like it is coming on (both with the relay and with the bypass). No CEL. The tach moves ever so slightly when I turn the key to ON position, regardless of whether it starts or not � ie up to 0 rpm. When I then crank the engine and the car DOES successfully start I see a subsequent tach bounce (eg up at around 200ish and then it goes up to 1000rpm on ignition). But when I crank and it does NOT start I see no tach bounce. If I understand correctly, this is what a crankshaft position sensor fail looks like? Is there anything else I can/should do to check this prior to replacing the CPS?

POST 2Original post

Yes, the tach needle should bounce about 1/4" or so while cranking. If not, it's likely a bad crankshaft position sensor.

This is a source reference. Confirm exact model applicability in the original material.