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91 TBI Issues - Lean?

dhcomp

dhcomp

1 ton status
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Hey Guys,

I'm a long time member on CK5, but never ventured into this forum.

I have a 91 V2500 burb with a new GM crate motor 15k ago.

Motor is stock, except the following:

TBI Spacer
Salad Bowl Intake Mod
Injector Spacer
Adjustable Fuel Pressure Regulator - Currently at 15, but normally at 13.
Edelbrock TBI Manifold
Flowtech Headers
3 wire O2 to fix o2 code after header install

Long story short, my truck runs hot. 200-210 cruising, up to 235+ towing up grades, etc. Last motor ran hot too.

Full story at: http://coloradok5.com/forums/showthread.php?t=298869&highlight=overhaul+cooling


Has always heated up quickly, even stock. Cooling upgrades are as follows:

Ac Delco Water Pump
High Flow 195˚ tstat
AC Delco HD Fan Clutch
Champion Radiator, CC716, 3 Row All Aluminum
50/50 coolant.
Water Wetter Additive
Factory Oil Cooler in front of rad, and same cooler on passenger side for trans

Replaced the ECM a couple years ago to fix a weird intermittent stumbling issue. ACDELCO 88999179 Engine Control Module (ECM Computer)


So, recently it was suggested i unplug my o2, and by chance, see if it runs better on the "default" program. Nothing really happened.

So, here i am. What can i do to further troubleshoot this? Is their a diagnostic ohm reading i can take on the o2 wire to make sure its registering like it should at the computer?

Any suggestions on attacking this from a tuning standpoint? I'm a big fan of simplicity on this truck, and just want it to cool properly. With the cooling upgrades I have, this thing should be bulletproof.

Not excited to get into any custom tuning, but figure its worth a shot. Or, at least i should do some data logging, or setup a wideband o2 to see what is going on. All stemming from the idea that running lean would make it run hot.

Any ideas?

I'm willing to try just about anything, as this has been going on for years, and is keeping me from being able to rely on my truck to tow when i need it. I've literally replaced EVERYTHING, and have no idea how to proceed forward.

Thanks guys!
 
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Subscribed. Also, you might try over on thirdgen.org. They have a pretty big TBI section.
 
Could be the temp gauge is off? If you data log it will tell you the temp it's running at...
 
I suppose technically you could watch O2 sensor voltage with a meter (would need long probe wires of course) while driving if you spliced into it, and/or you could watch CTS ohms while driving to correlate temp coming out of it. I'm no fan of splicing into wires though, honestly datalogging is easier and cleaner.

Is anyone around you that has the stuff? As I recall you run apple stuff, so PC won't work?

Now that I think about it, and if I can find it, my Autoxray XP240 would probably be useful for you if you want to borrow it.
 
eagle mark said:
Could be the temp gauge is off? If you data log it will tell you the temp it's running at...
Click to expand...

Ooo, a good reminder. I also installed a mechanical temp gauge, and ran it on the windshield for a while to verify the stock gauge. Its accurate.

Extra gauge is now under the hood, but still checked occasionally to verify stock unit.

How do the wide band o2's work? I think scott may have the setup, he's close to me.
 
Wide bands are pretty much the same as a narrow band other than they need a controller, are more expensive, and are accurate outside of 14.7:1 AFR, unlike the stock narrow band O2's.

Realistically for testing/diagnostic purposes, seeing if the engine is running lean with a narrow band is useful and easy, but any sort of datalogger/scanner/multimeter can allow you to do this. Simply watch voltage under steady state heavy throttle conditions.

Wide bands are extremely useful, but for tuning. They serve no advantage (that I can see on our old junk) outside of that. If it's free and easy to get hold of it would be useful.
 
Depending on where in motor the sensor is mounted you can get 20* difference?

The CTS for the EFI is mounted in intake right next to thermostat. The gauge is in drivers side head. Even those two are a little differant but there a big difference at back of intake...

So apples to apples... or...

If your O2 sensor is in good working order when your Closed Loop you can't be lean, only Stoich which is 14.12 to 1 AFR with E fuel and 14.7 to 1 AFR on non Ethanol...

Now if it is starving for gas on tow hills then it could go lean. So data log would tell a lot. But if it were running lean on a big hill it should set a code!!
 
I haven't ever looked into any sort of data logging stuff for OBDI.

Does it go through the OBDI port?

What type of cable is it on the computer side?

Are there any good bluetooth setups for non android devices?

I clearly know nothing about this stuff. I have a PC kicking around, but the battery doesnt' work, so I'd have to setup some sort of inverter.

Hm, maybe i can borrow one from work for a while.....
 
Well like I said, if you want to use my scantool (provided I find it shortly, shouldn't be too hard) you'd be welcome to borrow it, I'd just mail it to you. Little use for it with my datalogging setup. It's a lot handier though, which is nice.

Yes, the datalogging stuff goes through the ALDL port. Compute rside stuff I've seen is serial or USB.

Mark, it will set a code for lean even under WOT? I was under the impression (from my experience with my setup) that they wouldn't. Not saying I'm right, I just hadn't run into that before...I thought the O2 was essentially not used under PE conditions.
 
dyeager535 said:
Well like I said, if you want to use my scantool (provided I find it shortly, shouldn't be too hard) you'd be welcome to borrow it, I'd just mail it to you. Little use for it with my datalogging setup. It's a lot handier though, which is nice.

Yes, the datalogging stuff goes through the ALDL port. Computer side stuff I've seen is serial or USB.

Mark, it will set a code for lean even under WOT? I was under the impression (from my experience) that they wouldn't. Not saying I'm right, I just hadn't run into that before...I thought the O2 was essentially not used under PE conditions.
Click to expand...

Borrowing a scan tool would be great, as long as I know what to do with it.

Guessing it will give me live data updates, but won't log it? So, i'd just keep track of what i am seeing?

I appreciate the offer. I want to decide if I will buy a data logging setup before i have you send it though.
 
Is the best way to data log still a PC, and a usb ALDL cable, like sold on ebay?

If so, i think i need to probably head down this path.

Next tow will be a week from friday, so trying to plan ahead to have what i need on hand.
 
Data logging is free. Just download tuner pro. And you can borrow my cable if you want. Or you can buy one for about $60.
 
Which cable did you buy?

Appreciate the offer to borrow, but this is looking like it may take some time to figure out, so i may buy one.

Weighing the Bluetooth ALDL setup (if i can find an android device to sync with), or going with the usb cable.
 
I got it from aldlcable.com. I don't remember which exact one but the site tells you what one you need.
 
Ok. The android tab I thought I had access too isn't available. Going to go the USB route. Need to read on that site.

What software generates the best logs for all you tuner geniuses? Tunerpro?
 
dyeager535 said:
TunerPro I believe is the one you will get the most support for. It (and EagleMark) will do everything you need to with TBI. :)

Eaglemark runs this forum, I'd recommend buying the cable here http://www.gearhead-efi.com/Fuel-Injection/showthread.php?1592-Support-The-Forum-Buy-ALDL-Cables!
Click to expand...

Great tip. Canceled my other order, and ordering one from here.

Love supporting the "right" people.

:waytogo:

Ordered!

Edit: The gearhead efi one is out of production for a few weeks. I placed an order through the ALDL people, as I want this before the next big tow.

We'll see how it goes!
 
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There's a beginner TunerPro RT Tutorial as a sticky in this forum, just start with the data logging side. The other side is all you need to tune a chip. Download TunerPro RT and I will email you a set of my files. PM me your email.
http://coloradok5.com/forums/showthread.php?t=302680

We encourage people to pay the $39 registration fee so the author keeps interest in updates. Try it out, the more you use it the more you'll see it's well worth the $39.

Cable installation got harder because of chips and new drivers, but it's all here:
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?1557-Cable-Installation-to-TunerPro-RT

TunerPro RT is the best scan-tool and data logger you could have for these trucks! :waytogo:
 
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