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Old 07-28-2012, 05:16 PM   #16
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Quote:
Originally Posted by cocobolo95 View Post
What Bob meant by park position is where pcm commands iac when car starts. The other tb he was talking about was used on tuned port injection on 3rd gens from 86-92. The tb used was different than lt1 tb. And some aftermarket tb's are made to L98 specs rather than LT1.
Cool that's what I thought. I defiantly have an Lt1 throttle body never had tpi
Went from tbi to lt1
Will tinker with the tps wire today and see if it fixes my no start when hot
and high idle at stoplights. I'm guessing the wire expands enough to loose contact once it's hot and the pcm doesn't see a correct tps reading and thus won't stay running unless I throttle it up.
If it doesn't fix it I guess I will move on to the map sensor since all the other sensors are either new or work perfectly and I haven't paid much attention to the map readings
She runs excellent though even with the 3:23 gears its spins second gear and by that time i'm doing around 60.
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Old 07-29-2012, 02:32 AM   #17
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Wiggled the wire enough that now it doesn't want to stay running.
Ordered a new pigtail.
Going to try to solder new wires onto the tps. As a temporary fix until the pigtail arrives.
I think this will fix the idle a bit and hopefully some other issues.
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Old 07-29-2012, 07:14 AM   #18
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If you solder wires to tps, be sure to use an alligator clip or hemostats between tps and where you solder. Electronic components, like whats in the tps, do not like the heat of a soldering iron.
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Old 07-30-2012, 07:07 AM   #19
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Try here for replacement map sensors cooling temp IAT etc.

The link or url I tried to post will not post correctly. Go to amazon.com enter car specs then type of part. some of the best prices I've seen especially on MAP sensors.
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Old 08-02-2012, 02:12 AM   #20
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So the tps pigtail I bought seems to have fixed alot of my issues.
I still need to tinker with the throttle adjustment and such I have it at .88 volts for some reason and the throttle screw is open all the way and my iac is at 40.
It seems the Tps is now out of adjustment
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Old 08-02-2012, 05:41 PM   #21
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That voltage is a little high, but it should run properly at that voltage. The PCM takes values between .3-.9 to be a closed throttle, and should be indicated by a 0% TPS value.
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Old 11-06-2012, 06:25 AM   #22
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Still having this problem. After adjusting the tps it now starts and idles normally but when it heats up the rpms start to hang ???
Like going into open loop messes something up? 02 sensor? what could it be? So then I have to adjust the throttle blade closed more so it doesn't waste gas.
Then when I park it next time I start it it doesn't idle so the process repeats.
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Old 11-06-2012, 08:34 PM   #23
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Do what I'm going to do after some mods replace all the old sensors as you can afford. New TPS, IAC,AIT, MAP, Coolant Temp sensors, knock sensors and O2's. Could be a bug in the ECU or hidden short.
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Old 11-07-2012, 12:17 AM   #24
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I see what your saying, it already has a new iac and all of the other sensors appear to be reading normally. Will have to spend some more time cruising around with the scanner hooked up. It just sucks
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xegr smog catx aluminum ds Lca's & relocation brackets Adj. panhard pcmforless tuned

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Old 11-07-2012, 01:45 AM   #25
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Since you paid for a tune, I'd send your logs to pcmforless and have them take a look. I don't know how they claim it's not the tune without looking at your scan.

You could look at what's going on when it starts the high idle, what is the TPS reading when it's high? How about the AFGS? O2s? STFTs and LTFTs?


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1995 Firehawk #528 resto-mod underway

Planned 383 rebuild: 195cc competition LT4 AFR heads, custom cam grind (still debating specs), 6" or 5.85" rods, forged internals

Upgraded T56: Viper mainshaft and 2nd gear, steel 3/4 shift fork, Billet keys 1-4, bronze shifter cup, internals Cryo'd and REM'd
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Old 11-07-2012, 04:40 AM   #26
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Alright Here is what it does on a cold start

Camaro tryin to run - YouTube

After adjusting the throttle open so it stays running in open loop it then warms up and starts idling too high,
then I close them more and it still idles high and tends to die randomly when coming to a stop then won't start or will depending on my luck that day.
I'm assuming it runs out of air and the blades need opened more, but It's downright wrong to sit at a stoplight next to a prius with my catless lt1 humming at 1200 rpms. (nasty looks )

Anyway with the throttle adjusted back down and in closed loop it does this
Middle of the vid shows it idling and revving perfectly then I move it and it starts chugging barely idling twice! to avoid chugging I open the throttle blades and then it idles too high.

camaro 056 - YouTube

Here is the only vid i have of any data when it acts up but instead of idling at 500 and chugging it just dies.
It shows coolant at 198 and the map is reading okay i think at its lowest 43 or something. Intake air is really high because it never left the driveway idling too afraid to get stranded

camaro 058 - YouTube

Any advice? Iv'e tried messing with the tps and the throttle screw and such at closed loop idle to set the iac to no avail once started cold it does the same as the first video.

I guess the next thing to replace would be the o2 sensors but they switch fine and there is even a test on my ethos i can perform and they pass both with flying colors.

I am trying to be as clear as possible. I'm not the best at explaining what I am thinking and making any sense so you might have to read it twice if I sortof reverse engineered this post.

Will try and embed the videos but it doesn't always work...



P.S. Please help
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Hooker shorties, y-pipe & cat-back, 52mm tb, custom CAI elec wp
xegr smog catx aluminum ds Lca's & relocation brackets Adj. panhard pcmforless tuned

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Old 11-08-2012, 02:42 AM   #27
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The only thing I see is the IAC counts getting up in the 120's at times, but I imagine this is just the PCM trying to correct the idle rpm (can't see the rpm in that video and I'm getting no audio when I view it on my phone). Did you say the first video was from a cold start (open loop)? I saw on an earlier post you said it was fine until it warmed up and went into closed loop. Did you say the O2's were switching correctly even during the rough idle? What is the target idle to?

Have you checked for fuel issues? It would be a good idea to rule out a leaky injector, which would be more of a problem at low pulse widths (idle).

I'm not that experienced as a tuner, but I know there's tables for 0% TPS which control idle and deceleration, and deceleration fuel cut off (DFCO) tables which, if tuned incorrectly, can cause stalling when coming to a stop and idle problems.
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1995 Firehawk #528 resto-mod underway

Planned 383 rebuild: 195cc competition LT4 AFR heads, custom cam grind (still debating specs), 6" or 5.85" rods, forged internals

Upgraded T56: Viper mainshaft and 2nd gear, steel 3/4 shift fork, Billet keys 1-4, bronze shifter cup, internals Cryo'd and REM'd
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Old 11-08-2012, 03:04 AM   #28
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What is the closed TPS spark advance?
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Old 11-08-2012, 03:42 AM   #29
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Quote:
Originally Posted by 95 Firehawk View Post
The only thing I see is the IAC counts getting up in the 120's at times, but I imagine this is just the PCM trying to correct the idle rpm (can't see the rpm in that video and I'm getting no audio when I view it on my phone). Did you say the first video was from a cold start (open loop)? I saw on an earlier post you said it was fine until it warmed up and went into closed loop. Did you say the O2's were switching correctly even during the rough idle? What is the target idle to?

Have you checked for fuel issues? It would be a good idea to rule out a leaky injector, which would be more of a problem at low pulse widths (idle).

I'm not that experienced as a tuner, but I know there's tables for 0% TPS which control idle and deceleration, and deceleration fuel cut off (DFCO) tables which, if tuned incorrectly, can cause stalling when coming to a stop and idle problems.
The Iac is trying to compensate for not enough air the higher it goes right?
Sorry about the crappy video will make a new one when I find my scanner. I let someone borrow it.

It doesn't really have a rough idle per say it just idles down way too low and can be smoothed out by throttling it to the correct 950rpm I think it is set on.(or get out and open the throttle screw a bit)
o2's switch fine last i checked, the driver bank was a little lean before I fixed the welds on my headers. But switch fast as any other o2 ive seen. Regardless I will post a video asap that will be much better.
The second vid I think the screw is just a tad more closed then I have it set in the third one so it dies instead of idles really low like the third vid.

The only reason I ever messed with the screw was because it was the only way to get it to start and idle normally about 950, then once warmed up it starts acting up and idles up too much.

As for fuel I guess it could be an injector but It didn't have this problem before the cam swap and I didn't even take them off the rails.
It also has a new fuel filter and new walbro 255

guess I will pull the plugs and see what they look like too.

It has to be something I hope it is o2's or maybe plugs/wires.

The table tuning stuff your talking about i have no clue on
I see what your saying with the decel fuel and stop too but its not just that these videos are just in the driveway

I hate assuming but i feel like a sensor is reading wrong for closed loop and thats what causes it to change so drastically from cold to hot.
Plus it runs excellent minus the ability to idle at the pcm's desired idle.



Quote:
PA94Z What is the closed TPS spark advance?
Not really sure?> lamens terms like the idle (closed throttle) spark advance?
Or both the tps voltage and spark advance?

I have the tps set as low as I could get it I think .58 or something but it fluctuates depending on where the stop screw is (aka Me trying to drive it when cold or hot)

I feel like the car has been all over the place with this problem and I can't keep it straight in my head.
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xegr smog catx aluminum ds Lca's & relocation brackets Adj. panhard pcmforless tuned

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Old 11-08-2012, 04:28 AM   #30
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Closed TPS spark advance is the table the PCM uses for spark advance when idling. You should be able to see that under "spark advance" on your scanner.
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