westo Posted August 26, 2021 Share Posted August 26, 2021 I’ve recently done a conversion on my ba xr6 turbo to a 5 speed manual. Using auto wiring harness and bridged the gearbox wires, wires in the clutch switch and changed the parameters needed to drive it without going into limp mode, had moderate throttle hang when changing gears so I changed the idle air tables like it said in another post and also changed the dashpot over, I used the f6 ba turbo tune to compare, throttle hang is a lot worse now and it seems I have a dead spot in the throttle just as soon as I touch it, when I fully let off the throttle to change gears it spikes in revs but if I keep my foot on the throttle in this dead spot the revs drop as they should, I’ve data logged the throttle position and it’s showing no input when I let off the throttle but car still revs, I’ve also compared the idle and dashpot to a ba NA manual tune and still no luck. Car still drives fine otherwise so any help appreciated Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted August 26, 2021 Share Posted August 26, 2021 Smoke test the intake for leaks. What is your idle spark? If its below ~10 degrees you likely have an intake leak which would explain your rev hang etc and also your deadspot (no timing). Check torque sources to make sure you aren't in a limp mode or torque reduction mode. Check DTCs Check fuel pressure. 1 1 Quote Link to comment Share on other sites More sharing options...
Bill Posted August 26, 2021 Share Posted August 26, 2021 26 minutes ago, westo said: I’ve recently done a conversion on my ba xr6 turbo to a 5 speed manual. Using auto wiring harness and bridged the gearbox wires, wires in the clutch switch and changed the parameters needed to drive it without going into limp mode, had moderate throttle hang when changing gears so I changed the idle air tables like it said in another post and also changed the dashpot over, I used the f6 ba turbo tune to compare, throttle hang is a lot worse now and it seems I have a dead spot in the throttle just as soon as I touch it, when I fully let off the throttle to change gears it spikes in revs but if I keep my foot on the throttle in this dead spot the revs drop as they should, I’ve data logged the throttle position and it’s showing no input when I let off the throttle but car still revs, I’ve also compared the idle and dashpot to a ba NA manual tune and still no luck. Car still drives fine otherwise so any help appreciated I'm assuming your car is a factory turbo with the ABU-244 pcm. The F6 tune isn't the best tune to do a compare & copy due to it using BF sized tables & "Fully independent VCT" which aren't available in a stock BA turbo strategy. A manual BA XR6T strategy would be a better starting point for comparison. If you want to take advantage of the "Fully independent VCT" & BF sized tables, You'd be better off flashing the F6 strategy in. Quote Link to comment Share on other sites More sharing options...
westo Posted August 26, 2021 Author Share Posted August 26, 2021 Yer it’s factory turbo ba, I only used the air idle tables from the f6 tune, car idles perfect and revs perfect it’s just that throttle pedal, I tested the tps with another tb and it did the same, when you press in the throttle into that dead spot the butterfly goes backwards into the stopped car off position so I’m not sure if it’s tune related or a stuffed pedal Quote Link to comment Share on other sites More sharing options...
westo Posted August 26, 2021 Author Share Posted August 26, 2021 IMG_1070.MOV Here is a short video of what’s happening, ignition on engine off but this is what it’s doing when driving, press in the throttle slightly in that dead spot and butterfly goes backwards the data logger shows that the throttle is getting pressed and press a bit more on throttle and the butterfly operates properly, all data logging shows that pedal is working Quote Link to comment Share on other sites More sharing options...
westo Posted August 27, 2021 Author Share Posted August 27, 2021 1 hour ago, Roland@pcmtec said: Smoke test the intake for leaks. What is your idle spark? If its below ~10 degrees you likely have an intake leak which would explain your rev hang etc and also your deadspot (no timing). Check torque sources to make sure you aren't in a limp mode or torque reduction mode. Check DTCs Check fuel pressure. Toque soirée is driver demand, fuel is good, spark is at 2 degrees, so maybe a vacuum leak somewhere, done a quick smoke test but couldn’t see anything as yet, bout to check dtc Quote Link to comment Share on other sites More sharing options...
westo Posted August 27, 2021 Author Share Posted August 27, 2021 25 minutes ago, westo said: Toque soirée is driver demand, fuel is good, spark is at 2 degrees, so maybe a vacuum leak somewhere, done a quick smoke test but couldn’t see anything as yet, bout to check dtc No dtc fault codes either, might be a vacuum leak Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted August 27, 2021 Share Posted August 27, 2021 4 hours ago, westo said: Toque soirée is driver demand, fuel is good, spark is at 2 degrees, so maybe a vacuum leak somewhere, done a quick smoke test but couldn’t see anything as yet, bout to check dtc Spark at 2 degrees suggests you have a fairly severe intake air leak. The car will also likely overheat in summer like this. Sometimes leaks become worse when the engine torques over if the engine mounts are stuffed, as one side will pull on all the ancillaries and make the leak much worse temporarily. Being a BA it wouldn't surprise me if there were multiple small leaks. 1 Quote Link to comment Share on other sites More sharing options...
Plumbs Posted August 28, 2021 Share Posted August 28, 2021 (edited) If you have a vacum leak , wouldn't you also have a huge boost leak too? If that s the case , maybe pull one off the pipes off the cold supply side and rig up a bung with an air hose fitting . Then set your compressor to 10 psi and test ,( with motor turned off !) And you will soon find it. You could get a 90 mm fernco coupling and a 90mm test plug from your local plumbing shop . Then Hook up to your TB . Edited August 28, 2021 by Plumbs Quote Link to comment Share on other sites More sharing options...
westo Posted August 29, 2021 Author Share Posted August 29, 2021 On 8/27/2021 at 10:49 AM, westo said: Toque soirée is driver demand, fuel is good, spark is at 2 degrees, so maybe a vacuum leak somewhere, done a quick smoke test but couldn’t see anything as yet, bout to check dtc No dtc fault codes either, might be a vacuum leak. update I’ve replaced all gaskets, seated in the injectors properly and checked all vacuum lines, don’t have access to a smoke machine but I did spray all areas of manifold with aero start and no rev increase, taken car for a drive and still drives the same, I’m going to flash the old auto idle and dashpot back on and see if any changes Quote Link to comment Share on other sites More sharing options...
Roland@pcmtec Posted August 29, 2021 Share Posted August 29, 2021 Without a smoke test you may never find the air leak. I would not continue your diagnosis until you find one. 1 Quote Link to comment Share on other sites More sharing options...
Plumbs Posted August 29, 2021 Share Posted August 29, 2021 It’s not fitted properly. But I did for a demo . Hook up with motor stopped and use soapy water . We use the same method checking for Gas Tight in our installs . ( all be it 7 kpa in consumer piping ). another way is to get a vacuum gauge and see how vacuum you are getting . On my wife’s territory I get 17 inches . If your getting say like 9 inches of hg . You got a leak ? Yeh I know bit of a Plumber solution!! Quote Link to comment Share on other sites More sharing options...
westo Posted August 31, 2021 Author Share Posted August 31, 2021 Ok so done a smoke test with a homemade machine, no vacuum leaks I could find, I went back through the tune to check the dashpot and the idle and compared my current tune against the f6 tune and a NA 5 speed manual tune, the dashpot on my current tune doesn’t have any of the values or parameters as the manual tunes I have, I loaded the f6 as a compare file to my current tune and applied all the dashpot and all idle, going through the newly changed things on current tune and a few rpm parameters in idle airflow in gear and idle airflow in park/neutral are red which I assume they may be in conflict with other things that have been altered, might be fair to mention that the car has been tuned by a reputable local shop and the car has big injectors, big turbo and most of the bolts ons. I have saved the original tune on the car that I can revert back to if I manage to mess something up, as for the spark advance on data logger I might not of had it set in the right thing thus leading to the impression of a vacuum leak Quote Link to comment Share on other sites More sharing options...
westo Posted September 8, 2021 Author Share Posted September 8, 2021 Ok so done another smoke test, everything blocked up so no smoke could escape and nothing. I mentioned that it’s auto converted to manual and it seems I don’t have the idle or dashpot loaded onto the tune on the car, also noticed AUF2193 is still on the automatic value, also the idle spark is set to 2 degrees which is what the stock value is, I’m lost Quote Link to comment Share on other sites More sharing options...
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