454 TBI Swap 78 K30 Trouble with TunerproRT and Winaldl, etc.

[5cottymac]

Yes, I'm a newbie, been trolling on here for a while, just now registered. Searched for countless hours using forums and google, and I'm exhausted after trying to fix this truck.

Here is the background and I'll get on with the problems.

78 K30 Frame and Running gear, 454/TH400/205
88 S10 Cab,

My dad bought the truck a year a go to wheel while we dovetail, bob, shorten, and turn his 84 suburban on 1-tons into an 84 Avalanche. When we bought the truck it had a street avenger carb that someone had attempted to convert into a truck avenger. Truck ran good on flat ground, but sucked in the hills with fuel spilling out of vent tube into the venture. Truck would run rich on full throttle and very lean on part throttle. Ditched the carb, and bought parts to swap to fuel injection.

Howell Harness for 95 C3500HD 7.4L, and Prom to remove VSS and EGR functions
95 ECM, 16197427, BHMH Bin
95 GM OEM 7.4L Throttle Body

We installed the harness and all sensors. ( IAC, MAP, Heated O2, TPS, CTS). Running a factory style GM HEI....

Bottom line is, the truck runs super rich, and Howell has not been very helpful.

Using a Volt meter, as well as a borrowed OBD1 Scanner, we have checked all the sensors and everything is working correctly. Vacuum is steady at idle at 18.5-19". Idles choppy at 750-900 rpms. Small cam in 454, not too much overlap, considering idle vacuum. No other mechanical problems or vacuum leaks. Checked and rechecked all the typical easy fixes, and checked for leaks using propane, and found nothing.

The Heated O2 Sensor is in the Pass side header, just downstream of the collector, and measures around .89V at idle, pointing out the Rich Condition.
The Map Sensor voltage is between 1.5-1.8V at idle, again 18.5-19".
The Tps sensor was reading 1-2% at idle,
The IAC works and could been seen stepping in/out on the borrowed scanner.
The Base ignition timing is set at 12 degrees advanced with the connect closed (jumping out terminals)
The CTS is reading 298 ohms at 190 degrees, and 617 ohms at 150 degrees. Whether the engine is cold or warm, no change in AFR.

Fuel Pressure is 30psi, and the regulator works. From Howell -> 1995 HD 7.4 models used a higher 30psi fuel pressure to get needed flow from injectors. At first startup we had 15psi tbi pump and it definitely ran worse. Swapped to e2000 pump. Confirmed Regulator is working by pinching off return line and pressure runs up quickly. All new fuel lines so I doubt a blocked return line with the confirmed regulator operation.

As you crank up the truck the O2 sensor voltage starts at .45 volts and just creeps upward to .89-.9 the longer it runs. The exhaust will burn your eyes and is obviously rich, as well as plug fouling doesn't take too long. Tried 3 different heat range plugs with no effect.

Once engine is warm, when you drop it in gear, truck will stumble and stalls 50% of the time.

Replaced O2 sensor, TPS, MAP, and CTS and makes no difference. Only difference is truck runs better with the O2 sensor unplugged.

This brings me to building an ALDL cable per instructions on several forums. Can run it on either direct serial port or Serial to usb converter. Verified cable operation by plugging it in to 89 4.3L s10 blazer, and had all functions of WINALDL and Freescan. I have downloaded tunerproRT, Winaldl, and Freescan and nothing will communicate with the 95 ECM. The goal is to further diagnose the terrible rich condition by using TunerproRT as a glorified scan tool, and decide how to fix the truck, and get it to run better.

I downloaded the BMHM bin file, as well as the $0D Mask, and the $31 mask from this site.
Pretty sure I have done necessary steps with TunerPRORT but not positive because I have no communication with 95 ECM.

Also, when I try to open bmhm bin file, tunerprort says unable to open.

First off, not sure If I am doing correct things in the correct order with TunerproRT, and not sure if I installed the BIN file and Mask correctly. I'm not fluent with TunerproRT yet, but tested the ALDL cable using WINaldl on the 89 4.3, to rule out that it is a cable problem.

Any Ideas on why it is running rich? and Any advice appreciated on how to use TunerproRT with the masks for my ECM.

Thanks,
Scott.

[EagleMark]

If your getting a steady voltage reading from the O2 sensor then it's in Open Loop, no O2 sensor feedback to correct fueling. Will it go Closed Loop and see O2 sensor fluctuate when revved up? This would then do some fueling correction. If the fuel pressure is correct as stated then it's rich because of the tune. These 7.4L do like richer then normal at idle so it may be an Open Loop Idle bin? The narrow band is a good indicator but no where near as accurate when outside a very small range at .451v. Without a CAT everything smells rich to the human AFR meter we call a nose... Although fouling plugs is a bad sign and your right, to rich... How's it run other then that? Never mind do the next step first...

Set timing to 4 degrees advance with bypass wire disconnected. Not sure what you did but it is not correct way to set timing?

For the idle, what was IAC counts when warmed up after being driven? Should be under 30. For now you could turn throttle blade stop screw in 1/4 to 1/2 turn to let in more air to mix with fuel. This usually is a big help for idle quality.

You gave two different BCC? So I'm guessing at BMHM being correct as it is for a 95 7.4L engine. This is Maask ID $31 so you'll need that XDF and ADX file or you will not get correct communications for data in TunerPro RT.

This tutorial helps guys catch up to speed with TuenrPro RT.
http://www.gearhead-efi.com/Fuel-Inj...-a-must-read!-)

Since your cable is working the above instructions as well as this link below should get TunerPRo RT dialed in with your cable:
http://www.gearhead-efi.com/Fuel-Inj...to-TunerPro-RT

Then record the data, save it and can post it here so we can see what is going on!

HTH!

[5cottymac]

We set timing with the EST disconnected (Tan wire) initially at 4 degrees, and then disconnected battery per howell instructions. To get the truck driveable we set timing at 6,8,10, then 12 degrees advanced using the same methods in stages to track progress. The O2 sensor starts at .3 V and headed to just below .9v while running, idle and revved up. The fuel smoke coming from the exhaust was a better hint than my nose...that and fouled plugs saturated with fuel. We do have a nice conical spray pattern with injectors that are opening like normal. Im current using the $31 XDF, and $31 adx, and $31 ads file in Tunerpro. Ive also tried switching to $0E xdf and adx, and the $0D xdf and adx. I'm not positive that it ever leaves open loop. We messed around with the Iac and the throttle screw with howells advice and calibrating adjustments to ECM but no really effects were ever made. It still runs very rich driving it. I wish I were as rich as this truck...

I'm going off of that same tutorial to get going.

Pics are of ECM, and screen shots of all im getting with tuner pro.

Thanks Again, I appreciate it..

2a.jpg1a.jpg3a.jpg

[EagleMark]

What does CEL do when Key On engine off?

Look at top of injectors and get the numbers off them?

I've opened the BMHM bin file and in hex code it is $31. So use only those files.

Connection to TunerPro RT needs correct ADX file, cable installed on USB port, always use same USB port, look under Device manager in PC and see what Com port is assigned, go in TunerPro and make sure it is same Com port. Check cable connection with cable plugged into PC and not vehicle.

Something is wrong! duh, right? Adding that much timing to cover up an issue is on the dangerous side.

The BMHM chip is for a 4L80E transmission. So I hope Howell turned off more then VSS and EGR... even then I've done one of these type PCM without VSS and it was so much work to tune in person I'd never do it again! When you had Scan tool what error codes were set? Right now if injectors are correct numbers and CEL comes on, blinks and stays on till engine is started then goes off when engine is started? If not, or blinks when engine is started it's in Limp Home Mode, running that rich is what happens in LHM...

[1BadAction]

You have an XDF selected now? In that screen shot there is none selected. The timing needs to be set at 4 degrees and tuned from there if it is stock style ECM controlled. When everything is setup right, the tune will fall right in line.

Sounds like the injector flow rates are all screwed up VS the injectors that you are running. If you have the earlier BBC injectors in it, then you will be super rich just as you describe. Can you see any part numbers on them?

Edit: Looks like I was ninja'd by Mark :D

[EagleMark]

I also noticed that you cursor is pointing to Initialise Emulation Hardware? You don't have emulation? To connect you need to click on the Double Arrows, "Aquire Data (Connect disconnect) to get data...

[5cottymac]

I lost the paper i had written the injector #'s on, but i had previously looked up the color and verified the # to be the 94-95 7.4, lower flow rated, but higher pressure ones.

Every time I go through the process to select the xdf, it still shows at top no XDF selected. I follow the steps outlined in your tutorial I printed. The cursor over the initialize emulation is just a fluke. I was clicking the double arrow and all that changed was at the bottom: DA Not Connected to DA Connecting. I changed the com port in the tuner pro and did the test and it recognizes the cord.