2G How Often Do PTU’s Fail?

[GHSTII]

I’m troubleshooting, as I can’t get my car to start. It occurred to me that I haven’t thought to check the power transistor.

Any experienced minds?

Thanks.

 

[steve]

Given that in a stock setup they last decades but once people start moving they around and making other changes to the ignition system there are threads about them failing I'd ask, how are you using it and what diagnostics have you performed so far?

Having a good heatsync is important.

 

[GHSTII]

Replaced spark plugs, MAP sensor, wideband, battery, and today I re-grounded the PTU sensor. I've sealed any and all leaks. I've gone over the fuel tables, deadtime, ECU inputs, etc., so many consecutive times. I've had a couple tuners look at it remotely, and they've been very helpful. But of course, there's only so much one can help without physically being there, so I'm obviously missing something.

It's started up with a MAF setup before the build was finished, and it's just barely started up on this current Speed Density setup, though it ran super rich. I had to turn up the deadtime to the 700 range for it to turn over, but it wouldn't do it again. Highly unlikely it's a timing issue.

 

[steve]

So are you getting a spark? If so it's not the PTU.
Post a log since this sounds more like a first startup on a new setup type of issue.

 

[GHSTII]

10.01-01 is the one successful attempt on the SD setup. The one that ran super rich on the AEM UEGO Wideband.

10.14-12 is today with the re-grounded PTU and FT Wideband (only mentioning since those are physical changes). They also follow the most recent adjustments by my tuner.

Thanks for looking.

 

[steve]

Now days every time I see a 4 bar Omni MAP sensor I get suspicious.

I don't like those huge 11ms injector pulse widths when your cranking or the really low cranking speeds in the latest log. The IPW spikes follow the spikes in the MAP sensor and the ECU's computed airflow/rev. The airflow/rev value seems way out of wack.

I don't do SD so hopefully @1990TSIAWDTALON can take a look too.

The earlier log had both global deadtime and injector battery adjustments set which is a bad thing.

Perhaps I missed it but are you seeing spark? What do your plugs smell like?

 

[GHSTII]

Now days every time I see a 4 bar Omni MAP sensor I get suspicious.

I don't like those huge 11ms injector pulse widths when your cranking or the really low cranking speeds in the latest log. The IPW spikes follow the spikes in the MAP sensor and the ECU's computed airflow/rev. The airflow/rev value seems way out of wack.

I don't do SD so hopefully @1990TSIAWDTALON can take a look too.

The earlier log had both global deadtime and injector battery adjustments set which is a bad thing.

Perhaps I missed it but are you seeing spark? What do your plugs smell like?

Yeah, I knew I was taking drastic measures to get it to even turn over once. I wanted to see what it would take. Not at all ideal, so I know something has got to be wrong.

Plugs smell a bit of fuel. It'll still crank, but the real chugs are few and far between. Not getting enough of something to stay awake.

 

[chrysler kid]

I’m troubleshooting, as I can’t get my car to start. It occurred to me that I haven’t thought to check the power transistor.

Any experienced minds?

Thanks.

https://www.dsmtuners.com/threads/how-to-test-the-power-transistors.229419/