Hi,

I had my car apart to change fuel injectors so I decided to also remove my cold start injector and swap to an ARAP bin. So i removed the CSI and plugged the hole in the back of the fuel rail and now have the cold start injector plug unplugged. Is there anything else I need to do? Do I need to unplug the switch as well?

So I burned a chip with the stock ARAP bin. I deactivated VATS and changed my injector constant. Everything else untouched.

My idle is now over 2000rpm. I cannot detect any vacuum leaks. TPS is adjusted to spec. I tried to adjust the IAC. Car wouldn't start so i opened the throttle blades a little more, car still wouldn't start, so i opened them a little more, car started and went to 2500rpm, i backed down the idle screw all the way and it wouldn't idle below 2000 rpm. I have done this procedure many times in the past with no issues.

I do still have my old '87 350 memcal piggybacked to the ARAP chip. Is this maybe causing the problem?

I put my old chip back in and the car wouldn't start, it tried to start but never caught. Is the CSI really that important?

I could use some help, I'm really stumped.

Thanks,

John

 

Well I'm pretty dumb. I had two plenum bolts loose.

So I tightened all the intake bolts, and added 20% to the cranking fuel table for the '87 Stock Chip. Started right up this time. However I still can't seem to get it to idle under 1200rpm.

 

When I went from 32B to 6E all I did was burn a 6E bin (can't remember the exact bin, it was a 305 5-speed one as I had a 5-speed) and unplugged the cold start. Used the same 88 Memcal that I had before.

 

Thanks for the info.

I've been playing around with going back and forth between my old code and new. I was able to get the car to start with the 32b code by adding 20% to the cranking fuel pulse width. Sill have the high idle though.

So I think its more of a traditional high idle issue.

 

whats your TPS % at? supposed to be 0.54 volts

 

It is set to 0.54V

Funny thing, I put my chip in that I have been running the last 5 years, which was dyno tuned by Alvin at PCMForLess. And I was able to get it to stall by backing out the idle screw while doing the IAC Minimum Air setting. While if I use my new ARAP code or a stock '87 350TPI tune, I can't get it below 1200rpm while doing the minimum air setting. Strange.

Maybe the TPS needs to be adjusted for each chip? Sounds strange.

 

Nah this sounds like another problem here.. If it's set at 0.54 then it is probably working fine. There might be other code in the ARAP that changes things like timing and fuel settings that might affect idle?

 

Can you data log while it is idling high? Should tell you what RPM it is requesting. Could it be running in limp home mode for some reason?

 

I'll give it a shot when I get home. Come to think of it, I noticed with the 6E code that I couldn't get codes to read off the SES light, not even 12. I did not try for the other codes. I will try that tonight.

I have done some datalogging in the past but I have never been able to get it to work with TunerPro. So I have been using TTSDatamaster. This has been working for my old code but I could not get it to work with the 6E. I will try again tonight.

As for the idle issues, maybe for some reason the IAC isn't closing for the stock code or the 6E but is closing for my PCMForLess code? That is the only thing I can think of that would explain what I am experiencing. Tonight I will get the IAC closed with my PCMForLess code and then swap chips to finished the minimum air adjustment. That should be a good test.

 

You can adjust the IAC counts in a few places in TunerPro... Maybe that is what is causing some issues... Are you set up to do real time emulation? If you are then you could change some settings on the fly and see if it changes the idle or not. That's how I got my idle down to 700-750 and stable (I have a cam so I played with the MAF tables, but I also did some fine tuning in other areas). Also, does it always idle that high or is it only when it is warmed up or just started up? Do you have a bigger cam, did you remove the smog equipment, did you remove the EGR valve? These are all things that might contribute to higher idle if they are not adjusted in the PROM.

 

I think you may have misunderstood my point. While doing the IAC minimum air adjustment I can't get it to idle less than 1200 rpm with the screw backed all the way out. That is with the stock 32b chip and the ARAP 6E chip. If I put in my PCMForLess chip that i have been using the past 6 years, I can get it to stall out (500 rpm and less). So I think the issue is the IAC won't fully close with the ARAP or stock '87 chip, but will fully close with the PCMForLess chip, when doing the minimum air adjustment.

 

Okay, gotcha. What specs did the PCMforless chip have? High idle could be something other than the IAC.. Even if you back out the screw the whole way it might still idle high if there are other issues such as the ones I mentioned above like if you removed EGR and/or smog pump but didn't adjust the chip for the changes, then you may have a high idle. I had a problem similar to this, where the smog pump was removed and it idled high but then I bought a custom chip (back then before I did my own tuning) where they made the changes to the chip so that it recognizes that the smog pump was removed, and that made the idle drop down substantially.

I think what you need to do is look at each chip for differences and then figure out why the PCMforless chip is making the car idle high, although I don't see the PCMforless chip affecting the IAC any differently than the others, but like I mentioned above there are some parameters that do affect the IAC (I can't remember off the top of my head) but play around with those if you can (if you have live chip emulating then that makes it a billion times easier).

Hope this helps..

-marc

 

The PCMForLess chip is the one that ISN'T idling high.

What are you using for burning chips and datalogging?

 

Uhh yes I meant idling low! I wrote it wrong my bad!

I wanted to ask him to see the differences in the PCMforless chip and the other two to see why the PCMforless one is making the car idle low (i just had idling high in my head so i wrote it by accident! oopsie lol)

 

The example I gave where the smog pump was removed, and the chip accommodated for it, this is why it idles back down.. I was thinking that maybe the PCMforless chip had the same modifications to it that makes the PCMforless chip idle low, and the other two idle high. That would make sense to me..

 

Right, the PCMForLess chip is the only one that seems to be idling correctly. When I try to read what is on that chip, it just looks like gibberish. I think they do some hacker crap so you can't reverse engineer what they did.

I am using an Autoprom and Tuner Pro RT to burn the chips. I am a noob so maybe I'm just making dumb mistakes, but the car runs, so I must be doing something right. I have never been able to get datalogging working in Tunerpro, although I have not tried a whole lot. I am able to datalog the PCMForLess chip with TTSDatamaster through the autoprom. If I try to datalog the stock '87 chip or the ARAP chip, I get an error, "PCM connected, but data stream not as expected" or something like that. I'll try again tonight.

Car has working EGR. Smog pump has been removed as I use a modern Cat. I did not see anything in the bin where I could turn off the Smog Pump. Maybe that is my problem? I know when PCMForLess tuned my car I told them I do not have the AIR system installed.

Here is more details on the motor.
355 L98
TFS 195cc heads
Edelbrock TPI manifold
AS&M runners
stock throttle body
ZZ4 cam
10:1 compression

The PCMForLess tune was before the heads and TPI manifold were installed

 

That sounds similar for sure.

 

Also, for all three chips I'm using the stock ABWT memcal piggybacked on the new chip.

 

It looks like it could be the smog pump removal that might be the cause of the problem! Whatever they did to the PCMforless chip that tuned it to idle correctly without the smog pump, that's what you need to do to your current ARAP chip (or stock chip if that's what you want to use.) I'm sure if you hit up PCMforless, they would tell you how they did it considering you already bought the chip from them. If not, then there is a thread on here that explain this let me try to find it...

 

Interesting thread on this.. very old though..

https://www.thirdgen.org/forums/diy-...ete-final.html

 

And this might be how to fix it: https://www.thirdgen.org/forums/diy-...-pump-air.html

 

To answer your question on how to read chips with TunerPro and AutoProm, I actually had this question last summer and got the answer I was looking for here: https://www.thirdgen.org/forums/diy-...ml#post4698410

If you do it properly, then you will get real data and it won't be garbled anymore.

 

Sounds like the ECM is in limp mode. Try this to see:

At key-on, engine-off, observe the CEL/SES light. It should briefly turn on, blink off, then turn on solid. Can repeat the test after at least 10 seconds of key-off.

If the CEL/SES doesn't blink off the ECM is not running from the PROM, but is in limp mode. It must do the blink off. If not, then it is the only thing to work on.

This can be caused by an improper burn, or even the adapter that carries the chip. Was it from PCMsForLess or Moates? If Moates then it is OK. If from PCMsForLess there may be some signals crossed, which is why that chip reads as gibberish.

RBob.

 

I know I was not able to read codes, which I thought was strange. Also I noticed some a-typical SES light behavior. I think you may be correct.

The PCMForLess chip is actually on a moates adapter, looks like the G1, as supplied from PCMForLess.

The two new chips are on a Moates GP3 adapter. I believe I have the GP3 setup correctly to work as a pass through.

I guess I will try the PCMForLess tune on the new GP3 adapter and see what happens. I can then also try the new chips on the PCMForLess G1 adapter.

 

Could be the adapter is in the wrong way? Or not in all the way?

 

Once you get the idle sorted, you may want to correct the longer crank time that is written into the ARAP code. See the second post in this thread for the solution. It was amazing how much happiness that little fix brought me.

 

Ok, I made good progress today. I found out I was using the wrong addressing in TunerPro. I didn't know you had to change it.

Now the car starts off the chip and not limp home mode. Thanks to everyone for that.

However as soon as the car starts the SES lights blinks rapidly and continues blinking until i shut off the engine.. This is with my new ARAP code. Any ideas?

 

Another noob move. I had my A-B ALDL jumper in when I started the engine. That is why the light was blinking. Pulled it out now everything seems fine. No SES light, I get code 12. All seems to be good for now.

Thanks everyone.

 

Great to hear!

 

How's ur idle doin?

 

It came back down close to normal. I'll have to do the minimum air adjustment again now that things seem to be back to normal. Thanks for the help.

 

Sounds good man! Enjoy ur proper idling camaro!