VW AEB 1.8T Wired up, Crank signal woes...

[Glater91]

Ok,

Finished wiring my car up tonight. Everything is wired, grounds are perfect.

My issue is, upon cranking we are experiencing a random jump in rpm signal, I.E. 0-250 back to 0 while a steady crank is presented. This is resulting in failure to sync. This to us is quite odd. We have verified the wiring is correct on the crank and cam pos(also have seperate grounds on cyl head). EVERYTHING else is golden, output tests works great, coils/injectors fired perfect. TPS, IAT, CTS all worked and are calibrated throughout.

Engine mechanical timing is perfect. Ran perfect before on vw ecu with uni tune.

Car attempted to fire a few times, mostly ungodly loud backfires (intake/exhaust)

Timing was set to 114, 76 and 84 respectively. All with same jumpy tach results/backfires.

We suspect the failure to sync is being caused by the Crank signal.

Any help is greatly appreciated, also posting in diyautotune forum.


Thanks for your time,

Nathan

[prof315]

[prof315]

Having asked for an msq, looking at your tooth log you seem to have some false tooth detection going on. The MS3-Pro ( or a V3.57 mainboard) typically needs a 10K resistor inline on VR+ to get a clean signal with a 60-2 trigger CKP. Especially with VW 60-2 CKPs. Also start with a #1 tooth angle of 78 degrees and verify with a timing light, it may be off + or - 2 to 4 degrees but 78 degrees will ALWAYS get you in the ball park with a VW 60-2 trigger wheel.

[Glater91]

prof315

Thank you kindly sir, Please excuse that post, it was around 4am and we just wanted to hear the car breathe some life Not to mention I am unfamiliar with capturing/uploading .MSQ files. I was happy to capture and interpret what I did. (after MUCH more reading)

I am unfamiliar with all the ins and outs, we are learning tuning studio as best we can. Reading and diving in head on, taking notes and making sense of things. Working with a well versed turbo nissan tuner at the moment, and thankful for that.

Here's what happened. We mistakenly wired the Crank pos sensor wires completely backwards. Not sure how we got everything else correct, but to err is human. (esp @0430)

We set up all sensors again, verified timing and It fired up today, ran great!!!! Set timing according to the below instructions and verified with adjustable timing light.

We have encountered a high idle(~1500), identified a few vacuum leaks. I believe that the 4.6 throttle body is a bit large, but we will see. I have isolated and eliminated the sources of leaks. (Old oil cooler failed a while ago and ingested coolant into engine, so have been working on getting that crap out also) I am not running, and refuse to run an idle control valve. Unless someone knows of another manufactures aside from VAG that works great

Played with base timing to bring revs down a bit, with timing light got it set to 10 btdc, idled low but would not crank again. So reset it back and it fires up and runs great, just the high idle to sort now.

Thank you for the info, will post if we need anything else.

Respectfully,

Nathan

[prof315]

Ford IACs work pretty well with Megasquirt as do the 2 wire VW ones found on G60 Corrados, OBD1 ABAs and VR6s. The OBD2 ABA, AEG and VR6 throttle bodies with integrated IAC can be made to work as well (I use one) but it's a bit odd. A Ford 4.6L throttle body is a bit large, an OBD1 VR6 throttle body would probably work better.