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MaxDiesel

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About MaxDiesel

  • Rank
    IB Glitterati

Profile Information

  • Location
    West Sussex

Previous Fields

  • Current 911
    1987 Carrera 3.4 in Diamond Blue Metallic, 1973 Porsche 914 1.7
  • Favourite Food
    Italian
  • Drink?
    Good red wine

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  1. Thanks Phil ! 👍 If you do take the plunge with your engine then you're welcome to borrow any of the Porsche specific tools I've got - looks like you're not too far away.
  2. My rear suspension rebuild thread here:
  3. +1 For paint stripper - that’s what I’ve always used. Cover the pistons and leave for half an hour - then use scrubbing brushes etc Nitromors definitely isn’t as good as it used to be so I’d try and get a trade product. Toothbrush also works well for the ring grooves with no chance of damaging them.
  4. Sounds like you've got the air bleed very close then. Re the warm up fueling curve - yes Wayne will be able to adjust this. He'll need to start with the engine cold to do this - sometimes it can take a few warm-up cycles to get right. You could try adjusting the idle AFR using the mixture screw in the MAF controller - however any change you make will effect both hot and cold... so any adjustment you make to improve the cold/warm up rich running might make it too lean when hot. For this reason it's probably best to leave it to Wayne as he can change the shape of the fuel curve versus temp in the ECU.
  5. That's good - show's you're on the right track hopefully. The original air bleed screw in the throttle body allows very fine adjustment - I doubt the valve you have does the same so you'll probably need to tweak it in fractions of a turn... the acid test is having no change in hot idle speed when you remove the jumper wire - that shows you have it spot on. @SP72 Good call to check the CHTS - the temp reading from the CHTS is the main axis on the map that controls the ICV during warm up - so if it's not right it'll mess up the warm up characteristic. Another possibility could be... when it was remapped the warm up fueling curve was increased, versus MAF measured air, as there was un-metered air going in via the manifold leak.
  6. That looks just the job. Have you tried setting up the idle air flow with a bridge wire in the test port ?
  7. It depends what you want to do in the long run - if you want to be able to tweak the calibration yourself or use your local rolling road, then switching to a modern ECU is a big plus. The guys that can connect to 1980's motronic systems are few and far between now. We had a cupboard full of 1980's Motronic calibration equipment at work (e.g. Dataman S4).... unfortunately it all got binned in the late 90's when we didn't think we'd need it any more ☹️ You can get close to the same result with the original Motronic but you're reliant on guys like Wayne to get you there. Re the better refinement with an original AFM - he's right in some cases... it depends what your system is made up from. The original VFM units are naturally damped due to the weight of the barn door flap and the return spring. Consequently they give a very smooth volume flow signal that requires little or no software damping in the Motronic ECU. Some MAF units have built in electronics that discriminate between positive and negative flow (pulsation) and also apply some damping. Other MAF units output the raw signal and rely on SW in the main ECU to do all the signal processing - this is more common now as ECUs have so much processing power onboard. So - if you fit a cheap modern MAF, which has no internal signal processing, and apply a minimal signal correction to emulate a VFM signal it will not be good - the signal will fluctuate at a rate far higher than the ECU is expecting and you'll get driveability issues. I'm guessing Wayne has encountered some like this - hence his view. The kit I put together back in 2009 (Can't believe it was 10years ago!) uses an older generation MAF unit with onboard pulse correction and damping - even then we found the signal response was too fast for the Motronic ECU so we damped it further in the SW. Having driven my car with the kit on for ~7years I can't recall any refinement issues - the only glitch was not extending the altitude calculation far enough for the highest mountain passes in Europe... which RB kindly discovered for me 😉
  8. Yes - it's made a a direct swap unit for the existing Motronic unit - you could just fit and it would run along with the MAF control unit - although it would need re-mapping for you engine mods. With an adapter loom and a calibration update you could then remove the MAF controller (and map it again...). Its a shame you're so far away - I'd be happy to give you a hand setting it up with a Canems unit.
  9. There's some more info here from when I installed the Canems ECU on mine: https://www.impactbumpers.com/forum/index.php?/topic/31221-canems-innovate-mtx-l-install-with-maf/ You don't necessarily need the Lambda kit too - I mapped mine on the road so it was essential for me to be able to log Lambda along with the other ECU parameters. The Canems ECU has always had the ability to run with a MAF rather than a VFM - seems I was the first to give it go though. I think David at Canems has helped someone else with the same set-up - he was asking me of the part number of the MAF unit I'm using not so long ago. If you switch to Canems you also have the option of going to MAP based system and do away with the MAF too. I prefer MAF for accuracy of AFR control etc.
  10. That's sound advice. In the long run if you want to give yourself more mapping options and make the system simpler you could switch to a Canems ECU - this is what I'm running on mine these days with the MAF unit feeding directly into it (no separate MAF controller). It requires a short adapter loom from the MAF to the original loom - I can provide details for this. Anyone who's used to working with standalone ECUs like the ones you've listed should be fine with the Canems software - its pretty straightforward.
  11. OK - if they set the idle mixture already you shouldn't need to do again and won't need a Lambda gauge. You can still follow the rest of the steps above i.e. just skip steps 2) and 5). A quick test to see if you're on the right track would be to bridge B and C on the test port and see if it stalls or if the idle speed changes - if it does either of these then it shows you need to adjust the manual air bleed. In the long run I'd add a small breather air filter onto the bleed valve too.
  12. Sounds like your you still don't have the idle air under control. When the engine is cold the ICV opens to provide increased airflow during warm up. Below is what the ICV duty cycle versus engine temp looks like: If your ICV is already fully open at hot idle then its not able to provide more air when cold. This will happen if the manual idle air bleed is not providing enough air. The ICV needs to be in its nominal 'home' position at hot idle I'd recommend to go through the idle set up procedure again: 1) Fully warm engine 2) Attach Lambda probe / AFR gauge to exhaust 3) Bridge B and C with a wire: 4) Adjust manual idle bleed valve until you get target idle speed 5) Adjust the idle mixture screw on the MAF controller if required (This does the same as the idle mixture screw on the original VFM). Aim for ~0.96 Lambda (~14:1 AFR) - if unstable try going a little richer 6) Remove the jumper wire from the the test port - the idle speed should not change. If the idle speed does change refit the jumper wire and adjust the manual idle air bleed again. This should allow the ECU to control idle again - both during warm up and when hot.
  13. Sounds like you're getting there! I'm not 100% sure you'll be able to re-map the idle with the 3.2 ICV to the point where you don't still need a manual idle air screw. I'm assuming the 993 ICV has a higher flow range than the 3.2 ICV if doesn't need a throttle bypass too. Any permanent solution for idle air bleed will want to take filtered air pre-throttle and connect back in to the manifold post throttle - are there bunged ports pre and post throttle you can use for this? Failing that you could try adjusting the throttle stop to hold the butterfly slightly open... this may not be that consistent though.
  14. One more thing to check - have they tried adjusting the manual air bypass screw in the throttle body ? If there was an air leak before then the idle air screw may have been wound fully closed to compensate. If this was the case then fixing the leak would mean you now have insufficient idle air. The throttle air bypass screw should be adjusted with the ICV set to its mid position - this is done with a jumper wire in the diagnostic socket - I think there's a guide on Steve Wong's website.
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