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Hi guys,
So after putting up with an annoying idle characteristic for ages now, I've decided I'm going to try and fix it.
Car info:
6 bolt 2.0L with no balance shafts
Kelford 1-TX268 Camshaft set.
Bumped up compression (somewhere between 9.5 and 10:1 iirc. Its been a while since I built it).
Competition clutch chromoly flywheel, and one of their full face clutch kits.
Basically, when everything is up to temp, you can come to a stop, clutch in, and its mostly all good, with or without A/C on. With the AC on theres a noticeable RPM drop, down to maybe 800, which does make the car shudder a bit, but doesnt stall it.
But what I find is that after a warm start, the ISCV seems to be unable to 'catch' the engine as you clutch in with the A/C on, and the RPM's drop to 600 or so, which of course makes the car shudder and sometimes the A/C belt slips when you come back on the accelerator to help it (the squealing is the most annoying bit..).
It would just be nice to be able to come to a stop smoothly without the car shaking half of it's components loose!
I've had a bit of a read through old posts, but it seems 90550701 is missing a bunch of the idle tables. ISCV demand adder? RPM recovery? I've seen a few tables mentioned that I dont have. I've attached a screenshot of my tables (they're in order top to bottom to match the list on the left hand side). Now I understand the solution is probably to adjust the steps values in one or more of these tables. the problem is I've got nothing to start with, I dont know whether I should be working in steps of 1 or 10 for example.. and it seems a bit counter intuitive to me, why is the initial position with AC on LESS than it is with AC off? (14 vs 32 steps).
(I would play around with it, but it's kinda hard when I have to wait an hour or two for the car to cool off each time )
Any input is appreciated
I've attached a recent datalog from a warm-ish (pretty much cold) start, you should be able to see the RPM fluctuations if you have a graphing software like megalog viewer. This is a clutch in stop with the AC on.
This is a stop with the AC Off. The RPMs dont fall as far.
PS. Yes I've done all the expected stuff.. vac leak checks and all that jazz Rebuilt throttlebody with the engine, all new vac lines, standard intake system, recirculating BOV, Evo III ALS System with new vacuum tank.
Any queries, let me know.
Just realised it didnt upload the image of my idle tables..
mines5
That is the reason why i gave up on this rom long time ago
Which ROM would you suggest I use then? It was originally a 98640014 Evo 7 ROM. I'm not up to date on whats cross-compatible really. Went with the Evo 7 ECU because my Evo 3 loom plugs straight in (with the correct pin swaps and all the necessary parts of course)
Just realised it didnt upload the image of my idle tables..
Which ROM would you suggest I use then? It was originally a 98640014 Evo 7 ROM. I'm not up to date on whats cross-compatible really. Went with the Evo 7 ECU because my Evo 3 loom plugs straight in (with the correct pin swaps and all the necessary parts of course)
Buddy, I have been using 96530706 on all of my evo 7s, evo 6s, evo 5s, with e7 ECUs.
Works like a charm.
Dec 31, 2018, 08:48 PM
90550701 Idle Tuning
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