944 Turbo S Engine Rebuild Thread

[scam75]

My new ali rad provided all the same issues, was a lot of fun fitting it! It does offer a serious cooling upgrade though. In the cold weather I need to be stopped and idling in traffic for the temp gauge to reach a quarter, can only be good for maniacs like yourself chasing silly power!

Can you not make the middle undertray a piston catcher?

 

[Eldavo]

Ouch - the thought of taking an angle grinder to my car makes me shudder!

It’s not the first bracket or chassis part that’s needed a bit of “modification” - I’ve filed it down and neatened it up now, you can’t really see either cut with the intercooler pipes in place anyway.

 

[Eldavo]

My new ali rad provided all the same issues, was a lot of fun fitting it! It does offer a serious cooling upgrade though. In the cold weather I need to be stopped and idling in traffic for the temp gauge to reach a quarter, can only be good for maniacs like yourself chasing silly power!

Can you not make the middle undertray a piston catcher?

We’ve already established that the undertray can handle that one unfortunately.

 

[Eldavo]

Been pretty busy with work and life in the run-up to Xmas but managed to get the rest of the top end out back together.

Still to do: power steering pump/lines/belt/etc., air con pump/connections/belt/etc., coolant fill and bleed.




Before filling it with coolant I wanted to start the engine and check for leaks. Cranked it over on the starter with no ECU connected to build oil pressure - first issue found. I’d left the oil feed to the turbo loose in order to swivel it into position and the weep was the telltale - cleaned up and tightened that down.


Oil pressure from cranking:

 

[Eldavo]

Next up was to replace the fuel pump fuse and use VEMS to pressurise the system. Two of the injectors weren’t seated quite right and leaked. With the DanST fuel rail it was two Allen bolts to remove it, reseat them and recheck. Test now passed.



One thing I had noted when cranking for oil pressure was how slow it was turning over. I removed the cables from the starter, cleaned and reseated them but it still seems slow - even with a freshly charged newish battery and a jump pack - on a Hi Torq starter - further investigation with the multimeter required. VEMS is showing me 12.6v but the dash gauge is showing just above 10 with the red light on for low battery

Anyway - nothing ventured, nothing gained, I loaded up the config with the changes I’d made for the COP setup, said a little prayer and attempted to start the car.

Nothing.

Still nothing.

Consult laptop screen - no primary trigger detected.

Removed the single sensor, reset the gap (much more difficult with the wiring loom now in place) and still - Nothing.

Checked it was in the correct socket (I only use a single sensor into the speed sensor plug and the 60-2 toothed flywheel does everything else) but still no joy.

Peeled back the insulation and rubber boot on the plug to find it was completely goosed. Of course it would’ve been far far far easier to repair out of the car - perhaps at some point in the last few months when the look has sat in a cardboard box!

Anyway - new plug ordered from Amazon Prime, hopes of a Xmas miracle fading but still possible - gives me time to track down my low voltage/current situation at least:

 

[scam75]

Good progress, the voltage one is odd, good luck with that!

I had an annoying one wire no start after my rebuild, was eventually traced to the SciVision loom, the only non-standard wiring under my bonnet. One piddly little connector had unseated in the plug, and pushed itself backwards!

It does look like you've solved your no start issue but it will only be believed when the thing fires up! Not long........

Stuart

 

[Eldavo]

Pulled the starter motor and bench tested it, spinning up nice and fast. Checked the voltage at the starter end of the battery cable and it was identical to the voltage on the battery itself. Complete head scratcher as to why the voltage is showing so low on the dash (still reads fine on the laptop) and the engine spins over so sluggishly - answers on a postcard if you know where the instrument cluster takes the voltage from?

I was emptying out the garage and taking some stuff to the tip including the boxes I’d stored all the parts in. In the bottom of one was the wiring loom I’d removed for the wasted spark setup, and on the end of that loom was the plug I needed for the reference sensor!!!!

Chopped the wires, grafted them onto the old wiring and connected it up. Turned it over and it was trying to start but sounded like it was firing at 1/4 speed and still wouldn’t start. By now I figured it was probably flooded anyway so pulled the plugs and cleaned them up. Then connected them to the coils (pulled the fuel pump fuse again) and grounded them on the chassis before turning the key.

Somehow I had it in Harley Davidson mode and it was trying to fire on every lamppost rather than every stroke. Back to the laptop and figured it was maybe a Cam sync error - Peep suggested batch firing the coils in pairs and coming back to the cam sync signal in time so a quick fiddle with the settings and uploaded that to the ECU.

Given how sluggish it was to turn over I wasn’t expecting anything and didn’t even bother having my phone setup to record it. Just before I attempted to start it I removed a dried leaf from the bottom of the windscreen next to the aerial connection and chuckled to myself that maybe that was the problem all along . . . IT WAS! Started after about 3 seconds of slow cranking and ran really smoothly too. Let it run for 30 seconds or so (it was nearly 11pm and the garage doors were closed), before shutting everything off, locking the garage and the Xmas port got opened a day early, oh well it’s a Xmas Miracle after all.

Cheers and goodnight!

 

[blade7]

Well done, all down hill from now on .

 

[dlknight]

Sounds like an earth issue perhaps? What about the alternator connections? You did remember to put the large earth cable on the back of the engine?

 

[Eldavo]

Yeah, I think it’s an earth issue too - although the big earth is definitely connected.

Given the ECU shows the correct voltage (and the small grounds feed that) I think I’m narrowing it down to one of the main grounds. Either way, that can wait for a while.

Happy Xmas everyone

 

[blade7]

For quite a while I had an intermittent starter issue. Putting the car in gear and bumping it forward a little ,with the ignition off used to work. When I fitted a new starter, it did turn the engine over much faster.

 

[Eldavo]

I got all the remaining “underneath” bits done today - A/C compressor and belt on, power ateeeing pump and belt on and zip tied all the extra oil lines, etc out of the way too. Will need to run it before I lock the tensioners off though:



Realised I didn’t have enough power steering fluid and after working out it was Sunday (ChrimboLimbo issues) it was too late to get some so filled the coolant up and then found the brake booster heat shield as the very last engine-bay part to fit:




Removed the dipstick and a combination of nimble fingers and various angled long reach pliers had everything bolted up in place:

 

[Eldavo]

I have a new “Twbo” wing decal to fit and the strut brace - I’ll have a little ceremonial fitting of those once the engine is sorted. Whilst digging the decal out I found a 3l box of Cote de Provence Rose in my post-Le-Mans pile and promptly installed a “wine dispenser” by plonking it on one of my tool cabinets. That “L” may or may not be part of the Rolex signage from the Le Mans pit straight too :



Tomorrow’s job (aside from the power steering fluid) is to sort out some wiring - this looks a crazy mess but it’s not too bad actually. I’m removing the shift light as it doesn’t work with the new coil setup and also installing a bit of daft personalisation at the end of that yellow wire too using a VEMS feature:

View attachment 3381

 

[Eldavo]

Definitely the last post of the year - starts on the button and runs very smoothly although very rich. I do need to recalibrate the lambda sensor and check the map so it may be pretty simple.

I do have an oil leak from the turbo area though - thought it could be the feed pipe, but no. And the bolts holding the turbo in were tight so I messaged TTV saying I would have to remove the turbo to check/replace the seals.

I then sent him these pictures and (apologies to the 8v Twbo boys) realised that 38 minutes had elapsed from this:



To this:

 

[Eldavo]

Got to wait a whole year to order some new seals from Porsche now