fullymatted.
Back to search
911uk

Help - PSM and ABS failure warning

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

Discussion summary

YOUR RESEARCHHelp - PSM and ABS failure warning

Leading reported evidence

Replace maf and the brake light switch

Performed · outcome unconfirmed

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 performed work without a confirmed outcome
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.

Performed · outcome unconfirmed · Original poster

I've changed the MAF and the brake light switch.

Help - PSM and ABS failure warning
Frequently discussed work

Check wastegate

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

How do I check the wastegate?

Help - PSM and ABS failure warning
Read full discussion summary

Leading evidence: 'Replace maf and the brake light switch' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check wastegate' (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 · 10 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Replace maf so this is unlikely

Performed · outcome unconfirmed

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 performed work without a confirmed outcome
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.

Performed · outcome unconfirmed

You have already changed the maf so this is unlikely.

Help - PSM and ABS failure warning

Replace master cylinder

Performed · outcome unconfirmed

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 performed work without a confirmed outcome
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.

Performed · outcome unconfirmed

Fixed mine by replacing it, but cant see this making the engine run lumpy, car ran fine and then by coincidence starting throwing the ABS PASM light when I replaced master cylinder with a GT3 one from Mistercorn.

Help - PSM and ABS failure warning

Check wastegate

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

How do I check the wastegate?

Help - PSM and ABS failure warning

Disconnect maf makes the ecu

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

Disconnecting the MAF makes the ECU run a standard programmed in map.

Help - PSM and ABS failure warning
Frequently discussed actions (10)

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

Check wastegate

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

How do I check the wastegate?

Help - PSM and ABS failure warning

Disconnect maf makes the ecu

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

Disconnecting the MAF makes the ECU run a standard programmed in map.

Help - PSM and ABS failure warning

Replace maf and the brake light switch

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
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.

Performed · outcome unconfirmed · Original poster

I've changed the MAF and the brake light switch.

Help - PSM and ABS failure warning

Replace maf so this is unlikely

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
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.

Performed · outcome unconfirmed

You have already changed the maf so this is unlikely.

Help - PSM and ABS failure warning

Replace master cylinder

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
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.

Performed · outcome unconfirmed

Fixed mine by replacing it, but cant see this making the engine run lumpy, car ran fine and then by coincidence starting throwing the ABS PASM light when I replaced master cylinder with a GT3 one from Mistercorn.

Help - PSM and ABS failure warning

Run bad

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

The ECU is getting a dodgy reading off something that's causing it to run bad.

Help - PSM and ABS failure warning

Run lumpy at idle due

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

However in the meantime, If the engine is hunting, it could be a vacuum leak to the servo, as part of my fault finding, I pulled the vacuum pipe out of the servo and this caused the engine to run lumpy at idle due to the air leak.

Help - PSM and ABS failure warning

Run lumpy, car

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

Fixed mine by replacing it, but cant see this making the engine run lumpy, car ran fine and then by coincidence starting throwing the ABS PASM light when I replaced master cylinder with a GT3 one from Mistercorn.

Help - PSM and ABS failure warning

Run on default values

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

Unplugging a maf as said will make it run on default values ..

Help - PSM and ABS failure warning

Run standard programmed in map

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

Disconnecting the MAF makes the ECU run a standard programmed in map.

Help - PSM and ABS failure warning
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.

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

  • 911uk: 1 discussions

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

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

Generation: 20261026T203514Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Help! I took the 996tt out for an MOT today. It passed. As I was driving back I pushed the car and all of a sudden the power dropped off and the engine cut out as I was coming to a roundabout. I restarted the car and the lights were saying PSM failure and ABS failure - drive to workshop. I drove it back home (2 miles) carefully and parked it in the garage. I noticed that the engine was hunting and cut out? Any ideas what this could be? All advice appreciated.

POST 2Original post

Get it on a PIWIS tester asap. This will show the fault codes. I have been having fun with ABS lights coming on with my C4 which has the same brake set up as yours. Am sure DeMort will be along soon with sagely advice. However in the meantime, If the engine is hunting, it could be a vacuum leak to the servo, as part of my fault finding, I pulled the vacuum pipe out of the servo and this caused the engine to run lumpy at idle due to the air leak. Further things to look at are Brake light switch, which can throw up fault codes. Fixed mine by replacing it, but cant see this making the engine run lumpy, car ran fine and then by coincidence starting throwing the ABS PASM light when I replaced master cylinder with a GT3 one from Mistercorn. Nothing wrong with the master cylinder, however a new fault code appeared 4460 which is the ABS unit pressure sensor sending random pressure readings from 0-14 PSI to the ECU. The ECU cannot understand the readings and throws up the ABS/PASM light. In fact the DHL man has just collected my ABS unit which is heading off to ecutesting at Heanor near Derby for testing and repair. Other causes can be wheel speed sensors (wiring is vulnerable) and the MAF sensor. So it can be infuriating snagging this if you do not know the fault code, so suggest you get it to nearest Indy who has a PIWIS system to read it. I have tried other systems, but they are too vague with their analysis, telling you that you have a brake system issue, but not what it is Hope this helps (?) and dont worry you dont have to set fire to it...yet!! :frustrated: :frustrated:

POST 3 / ORIGINAL POSTEROriginal post

Thanks Stuart, I've changed the MAF and the brake light switch. Still have the same error codes. I've also plugged in a friends OBD II and its coming up with P1250. :roll:

POST 4Original post

If the engine is hunting and playing up it won't have anything to do with you ABS/PSM system. It's an engine problem. Disconnect your MAF and see how it runs once it settles down (few seconds)

POST 5 / ORIGINAL POSTEROriginal post

Hi Alex, The car runs better with the MAF disconnected. Just to make sure I connected it back up and then it started to hunt and then stalled. Any ideas, noting ABS and PSM light are on. Thanks

POST 6Original post

That code seems to be overboost detected. Have you checked that your waste gates are free to move and not corroded shut? You have already changed the maf so this is unlikely. N75 valve may be a good shout too, as well as some boost leak checks. If not get it to a good indy for a view. Good luck.

POST 7 / ORIGINAL POSTEROriginal post

Thanks, How do I check the wastegate? What does that fact that the car runs better when the MAF is removed, with the MAF it stalls (noting new MAF)? Thanks

POST 8Original post

Disconnecting the MAF makes the ECU run a standard programmed in map. The ECU is getting a dodgy reading off something that's causing it to run bad. This will also trigger abs faults. Could be maf reading or an engine/exhaust sensor.

POST 9Original post

Unplugging a maf as said will make it run on default values .. but this doesn't mean the fault is the maf as it can mask other faults by doing this ... ie air leaks . Your fault code is listed here but with the non standard items you have then i'm a little out of my depth and it might be more of a question for 9E to answer . http://911uk.com/viewtopic.php?p=510426

POST 10 / ORIGINAL POSTEROriginal post

Just a quick update. Looking under the car, I found that the silicon house to the inter cooler had come off (seems the garage had not fitted it properly). I have refitted and hope its stays on. Removed codes using OBD reader and restarted the car and it all seems fine. I will take out when the weather is drier. Thanks to everyone for your advice. Mucho appreciated. :thumbs: :thumbs:

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