ARAP $6E Smoother Idle?
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Joined: Aug 2010
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From: Hamilton Ontario
ARAP $6E Smoother Idle?
Hey All.
86 Coupe..stock L98...egr...air and cold start injector deleted/removed
i switched over to an 89 ARAP $6E From my stock $32 BUA.
Made a few minor changes in the tune like fans on/off..Vats delete//egr delete..
I also tweaked MAF table #1 to obtain close 128/128 BLM... not bad at all.
Left pretty much every else in the ARAP the way it was.
My issue is that my idle is no where near as smooth with the ARAP as it is with my BUA32. The arap idle does settle down a bit after it warms up, but with the 32 bin..it is very smooth from cold start until finish.
What can i look at changing in the stock arap bin to obtain a smoother idle?
Did the idle reset proCedure and everything is in order. TPS AT 0.55V...Timing is at 6 BTDC...IAC Counts are around 20ish at idle fully warmed up...sprayed MAF cleaner in the sensor...cleaned throttle body and passages...fuel pressure is good..42 key on...38 while idling...injectors (new FIC) all ohmed at 13.6 cold
86 Coupe..stock L98...egr...air and cold start injector deleted/removed
i switched over to an 89 ARAP $6E From my stock $32 BUA.
Made a few minor changes in the tune like fans on/off..Vats delete//egr delete..
I also tweaked MAF table #1 to obtain close 128/128 BLM... not bad at all.
Left pretty much every else in the ARAP the way it was.
My issue is that my idle is no where near as smooth with the ARAP as it is with my BUA32. The arap idle does settle down a bit after it warms up, but with the 32 bin..it is very smooth from cold start until finish.
What can i look at changing in the stock arap bin to obtain a smoother idle?
Did the idle reset proCedure and everything is in order. TPS AT 0.55V...Timing is at 6 BTDC...IAC Counts are around 20ish at idle fully warmed up...sprayed MAF cleaner in the sensor...cleaned throttle body and passages...fuel pressure is good..42 key on...38 while idling...injectors (new FIC) all ohmed at 13.6 cold
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Joined: Aug 2010
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From: Hamilton Ontario
Melting Slicks
Joined: Aug 2011
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Your description running bad is very vague. IIRC but had less timing than arap that is a contributing factor. With iron heads you should just use aujm look at the sa and maf table differences.
Last edited by Tunedport90; Aug 7, 2013 at 01:29 PM.
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From: Hamilton Ontario
So, i downloaded the AUJM and burned it without making any changes..car started up fine but fan was running instantly..something not right...tried the same file with 2 other chips..same results..downloaded 2 other AUJM bins from different sources...3 chips..same results...fan comes on??
Is there something i need to change in that bin before i burn it for my car?
I had some wacky results with the ABTT $32B bin from an 88...burned the chip using the 32b .xdf without changing anything in the bin...car started and ran well for awhile...then the engine just quit cold in the middle of the road (never done that before)...started right up again...my car does not like these 2 broadcast codes...unless im burning them wrong?
Is there a Need to change anything in the bin before burning the chip...prom I.D. or anything?
Last edited by raiderz; Aug 7, 2013 at 03:06 PM.
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From: Hamilton Ontario
Unchecked it..burned chip and it seems to idle a touch better than the stock ARAP,,,Drove it for a whole day and was not too impressed with idle...$32 bua gives me the best idle on the same engine?
I looked at the SA able for the AUJM..some low timing numbers there...strange looking table...maybe from a Cavalier or something? lol
Anyways just for kicks i copied the SA table form the AUJM into my ARAP bin and burned a chip.....WOW....very nice idle improvement over the stock ARAP...pretty comparable to the smoothness i get with my $32.
I running slightly rich at idle AND LOWER rpm now (124 BLM ) due to the new table i guess?
Nothing serious though...i will drive it like this for a few days and see how she goes...
Thanks Tunerport90
Drifting
Joined: May 2013
Posts: 1,736
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From: Reno Nevada
Modify the arap spark table to mirror the bua at and near idle. I would think this would solve the problem.
Edit: I just looked at BUA1728. Why not just copy the entire spark table into the ARAP, and then zero out the ARAP's power enrichment spark advance.
Edit: I just looked at BUA1728. Why not just copy the entire spark table into the ARAP, and then zero out the ARAP's power enrichment spark advance.
Last edited by MrWillys; Aug 8, 2013 at 05:11 PM.
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Thread Starter
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Joined: Aug 2010
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From: Hamilton Ontario
Its only slightly richer at idle...i kinda like it there...BLM at 124...no sweat..
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From: Hamilton Ontario
Tonight, I copied the SA table from my stock BUA9340 bin and pasted it into the ARAP...ZEROED out the enrichment table for all RPM fields...put the chip in fired it up...took it for a short run...did not datalog...car ran nice...idled pretty well, but the engine was already fully warmed up. Will fire it in the morning and take it for a run...maybe do a datalog also to see whats happening.
Will post results tomorrow
Thanks Guys
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From: Hamilton Ontario
Im back from Vacation and car still has a "choppy" idle.
None of the bin combinations seem to work great.
I put my $32 BUA back in and even now this bin does not give me a satisfactory smooth idle?
When i think about it... this "crappy" idle started shortly after the shop installed a new P/U Coil in my distributor...I wonder if they installed it correctly or fubared something else in the process?
I "thought" the car ran pretty well a few days after i got it back...not too sure though...haven't driven it all that much lately.....
Ray
None of the bin combinations seem to work great.
I put my $32 BUA back in and even now this bin does not give me a satisfactory smooth idle?
When i think about it... this "crappy" idle started shortly after the shop installed a new P/U Coil in my distributor...I wonder if they installed it correctly or fubared something else in the process?
I "thought" the car ran pretty well a few days after i got it back...not too sure though...haven't driven it all that much lately.....
Ray
Melting Slicks
Joined: Aug 2011
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it does sound like a ignition issue, coil breaking down, too much plug wire resistance or plug condition or gap. You can only install the icm one way but if you didnt wipe dielectric grease or heats sink compound under the icm the heat will kill it fast.
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From: Hamilton Ontario
Distributor was removed from the car and dismantled to install the P/U Coil (problem started shortly after this "i believe")
ICM (HEAT SINK COMPOUND)...Ignition Coil...Taylor Wires...Bosch Platinum plugs...all new this summer.
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From: Hamilton Ontario
So i got bored yesterday and decided for the hell of it to check the timing...and sure enough...it was barely hanging on to 4BTDC. I turned the dist very slightly to hit 6BTDC and the idle smoothened right out!
"INSPECT WHAT YOU EXPECT"
I know i said earlier that the timing was correct...i did not check it as i assumed the $100 per hour i paid the tech to do my distributor P/U Coil would have covered that area..i guess not!!!
I went over to talk to the mechanic and he assured me he dropped the distributor back into the "exact" spot he took it out of...he even showed me the marks he made on my intake to line it up.
He said it must have been "retarded" to begin with.....i left that one alone....
I believe he must have been out at least one tooth...what do you think??
I know for sure he did not put a timing light on it like he should have!!
Anyways....car idles nice and smooth using either the ARAP$6E or $32BUA....happy..happy...happy
Thanks for following this thread
Ray
Drifting
Joined: May 2013
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From: Reno Nevada
There's no excuse in my opinion for not putting a timing light on it in my opinion.
If this has an aftermarket cam you might consider adding another 2 degrees in the spark table at idle to see if it gets even smoother.
If this has an aftermarket cam you might consider adding another 2 degrees in the spark table at idle to see if it gets even smoother.
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Joined: Aug 2010
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From: Hamilton Ontario
I believe this to be the stock cam..i have only had the car a few years and have no history...everything ASSSUMED to be stock...theres that word again...lol
I run regular gas for the most part so increasing the timing would not be advisable?
Do you think the mechanic placed the distributor back in "1 tooth off" if the car did not have the choppy idle before that?
Also..if the harmonic balancer "slipped" would that cause the timing to "move" or just make setting the timing more difficult to line up tabs?
The mechanic was also mumbling something about the HB...but di not elaborate if mine was faulty...looks to be in alignment...very very minor cracking in a few spots?
Drifting
Joined: May 2013
Posts: 1,736
Likes: 31
From: Reno Nevada
I don't think he was a tooth off, but 2 degrees is a very small amount, so if his mark was slightly off.
As long as you're running good I wouldn't change it. 2 degrees at idle wouldn't affect the operating portion of the table except maybe sitting at a light.
As long as you're running good I wouldn't change it. 2 degrees at idle wouldn't affect the operating portion of the table except maybe sitting at a light.
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From: Hamilton Ontario
Thanks for your opinion and ideas throughout this thread.
I might advance timing to 8degrees just to see how it changes things.
I do have this intermittent "hiccup" while sitting at a stoplight for an extended period..i have always had that little hiccup?
What do you think about the HB thing and how it changes or affects timing?
Ray
I might advance timing to 8degrees just to see how it changes things.
I do have this intermittent "hiccup" while sitting at a stoplight for an extended period..i have always had that little hiccup?
What do you think about the HB thing and how it changes or affects timing?
Ray