HI good people of SAABSCENE!

i have a on going project which was born out of frustration with my old NA engine, which was about to have a lot of cash spent on it. it was a 2.0ltr engine which would have been running Dbilas throttle bodies, ported head, agressive cams, uprated pistons, lightened flywheel, LSD'd gearbox, DTA management. but when i found a thread of thought that said the GM 900 had simialr links to the Vauxhall Cav, i thought as the egine was coming out to first try out a bit of Swedish forced induction.

Currently the engine has been in for a few months, and its done quite a few hundred miles too. Its not been plain sailing as I've found a few issues with some bits that arent quite working as they should.

I cant take the credit for shoe horning it in though, that was my friend Jim who did that

I was hoping that a bit of extra Saab knowledge might help with the few teething issues im having.

First off, it idles quite rough, and theres a tinge of black smoke, suggesting over fuelling. It started to happen slowly over time so im hoping its sensor related. Ive got a replacement idle control, lambda, DI cassette coming soon to try, and im wondering it the coolent temp sensor could be causing issues?

Second its not boosting right. on WOT you can here the turbo kind of spooling up then down then up again. ive got a gauge in and its showing only 0.5 bar or boost. so far i suspect the actuator arm as its very easy to move, so have ordered a forge one. what else could cause this?

Thirdly, and the most annoying is when slowing and dipping the clutch the car will almost certainly stall. we've now changed the throttle cable position when it helps stop that, but when you gentely start to accelerate it feels like the throttle goes from open, to closed, to open again, if if you dont accelerate fast enough it will stall. almost like we've opened it beyond the fully closed position (if that makes sense) when you disconnect the idle control the revs change so it seems to be working, and im getting another to try anyway. but its been suggested that the ecu needs a speed input, maybe from the abs sensor? then using t5 suite i can adjust the signal to get it spot on. its also been suggested that this will also stop the car reaching full boost.

lastly shes got a small oil leak, somewhere near the PAS pump. are these a traditional place for them to go?

the engine is really nice to drive, and so much better already than my outgoing lump. my OH has a vectra turbo'd by a vx lump, and hers is quicker, so i need to catch up!

Some pictures for you:







that last one was taken just after fitting the coilover suspension, ive not really had the chance to clean her up properly since last year due to the work going on. but shes nearly ready for a full clean up!

appreciate any suggestions

Welcome

What engine management are you running? Trionic or something else?

good old tronic 5


thought about using the dta but the tronic system is excellent!

OK, first thing is to check for any leaks. T5 is normally very tolerant of leaks but that doesn't mean that there isn't one somewhere causing a problem.

An over rich mixture could be caused by a faulty coolant temp or air temp sensor. Spec is as follows:



The boost problem may be down to a faulty actuator but it sounds more like a problem with the APC system. Check the resistance- it should be about 2.5-3ohms between pins 1-2 and 2-3. Try blocking the W and R ports whilst blowing through the C. You should only ever be able to blow through one or the other i.e. C-R or C-W. There should be no path from R to W.

Have you got the engine fault light wired in? That may give you some clues- there's a lookup table in the 9000 forum.

thanks for the info, no we havent got the check light working yet, might need to look into wiring into a seperate led and mount if somewhere, but havent worked out the pins for it yet.

was thinking once i have the pc sorted and the can lead i wouldnt really need it day to day