'87 350 TBI, custom application, looking to go bare-bones

[Mrgto68]

Here's my situation:

Back in 2014 I picked up an '87 r30 w/ 350 tbi to use as the base for a specialty vehicle I was creating. I have since radically modified the rig, including relocating the driver controls.

The vehicle never drives faster then 15-20 mph, averaging 5 mph, and most of the time during operation she sits at idle turning two high output alternators providing power back to 4 -12v "house" batteries.

The one issue I'm having is the motor runs very rich at idle and upon acceleration.

The old wiring harness was pretty beat up, and I wanted to keep things simple under the hood so I purchased a new wiring harness, new injectors, new o2 sensor, temp sending unit and Map sensor. When relocating the driver controls, the only wiring I brought up to the new driver location are the ignition wires. I installed new aftermarket fuel, temp and oil pressure gauges. Needless to say, I don't have the idiot lights ie: service engine lights etc. The new wiring harness does have the code reader, however I don't have a way to pull the codes.

I'd like to keep the tbi running with the bare min sensors, ie: 02, MAP, temp sensors. Which wires/sensors don't I need? What could be causing this extreme rich conditions? Could the ECM be in "limp" mode? Outside of the motor running rich, she has very little power, bogs down and really struggles to go over a speed bump at slow speeds and currently takes about 3-4 cranks to fire up. All of these issues began after installing the new wiring harness.

I don't have to worry about emissions either as this will never be registered as a street legal rig. Primarily for festivals, parades and special events so I don't need to run the smog pump etc.


Thanks in advance

[PlayingWithTBI]

Have you thought about finding a used manifold and carburetor and throwing them on? You'd have to drill out the center two bolt holes to accept the 72* bolt angle TBI manifolds use, throw in an HEI distributor and maybe a hand throttle to raise RPMs while charging your batteries?

[Mrgto68]

One of the reasons I chose the 87 R30 was for the 350 TBI. I will never own another Carbed Vehicle again. I restored a '68 GTO w/ 400 motor and after 15 years of carburetor adjustments I purchased a FiTech TBI system, the best $1,500 I ever spent. I just don't want to deal with all of the adjustments. I'm getting to old and technology has gotten that good.

[dave w]

I think it would be worth the effort and expense to have a TBI system running closed loop.

The necessary components for "Closed Loop":
MAP
TPS
IAC
CTS
HO2S (3 wire O2)
Distributor using an 8 pin ignition module
TBI Externally Mounted Coil

(optional?)
VSS
ALDL Diagnostics Connector (for data logging / reading trouble codes)
Knock Sensor
SES

Additional 1227747 ECM Information Link: http://www.gearhead-efi.com/Fuel-Inj...Information-42

dave w

[mecanicus]

What exactly did you have with the engine up to now.
Which ecm do you have?
The harness is from or for which car?
I have changed from carburator to tbi and o2 sensor would not start to work. It took me some hours changing 02 sensors and switching cables. At least I found the problem. Here on the forum you have a conversion sheet for the connection of cables when switching to an other ecm.A10 is plus from the o2 sensor and A12 is minus to the 02 sensor, but I had to connect minus to ground too,then the o2 sensor worked and engine runs in closed loop as desired. Have a look to this too.
As a newbie i had lot of problems getting tunerpro-rt to work. And tunerpro-rt is the only diagnostic programm i could connect to my ecm! Read the faq at tunerpro and have a look to the tunerpro forum. Data cable is very easy to build, just a usb-ttl converter ( should be 5 Volt version with fdti chip or P2102 from silicon labs, 3V china will often not work) and a socket to the car.
And the forum here is very good for further questions and help.

[Mrgto68]

I think it would be worth the effort and expense to have a TBI system running closed loop.

The necessary components for "Closed Loop":
MAP
TPS
IAC
CTS
HO2S (3 wire O2)
Distributor using an 8 pin ignition module
TBI Externally Mounted Coil

(optional?)
VSS
ALDL Diagnostics Connector (for data logging / reading trouble codes)
Knock Sensor
SES

Additional 1227747 ECM Information Link: http://www.gearhead-efi.com/Fuel-Inj...Information-42

dave w

Hey Dave, thanks for the info. the Rig has all of the original components under the hood. Which is what I'm assuming you listed that I needed? The new wire harness has the ALDL connector.

I guess the best thing for me to do is to find a way to pull the codes?

[PlayingWithTBI]

SES light and shorting pins A & B or TunerPro RT and ALDL cable

[Mrgto68]

OK, I ordered a OBD1 Cable and got all set up with WinALDL.

I logged a bunch of data and was hoping someone could glance it over for me. Dave W, i did notice it was flagging "closed loop"

i have the log.txt , BLM.txt, INT.txt, O2. txt and KNOCK.txt.

[dave w]

I strongly feel WinALDL is OBSOLETE! I haven't used in many years.

TunerPro RT is SUPERIOR in so many WAYS!

dave w

[S.O.B.B.]

http://www.gearhead-efi.com/Fuel-Inj...iring-question
Hope that's how a link is posted.

[mecanicus]

Up to now you still didn`t tell us which ecm you have exactly. Here:http://www.gearhead-efi.com/Fuel-Inj...ams-Tuner-Info!
you should find your diagramm. DRAC normally has 6 connections: two are coming from the transmission, two are plus and minus, two go to the ecm.
If you connect ecm and plus minus only, then error message should go.
If you want to delete the TCC you need a socket for an eeprom, a 27xx512 and a programmer like the moates one or the xgpro TL866.Or you ask here on the forum if somebody will settings on your memcal.Everything is described here in the first thread.

[Mrgto68]

Up to now you still didn`t tell us which ecm you have exactly. .

Sorry about that, I thought I posted it earlier. It has the 7747 ECM.


There were a few wire connections that I didn't connect as I wasn't sure it would matter at the time.

• Wire to Stop Switch (Should this be connected for my application?)
• Wire to Park / Neutral (Should this be connected for my application?)
• VSS Plug - Complete dash was removed and discarded, just ordered the 2PRS Speed Sensor from JTR
• TCC Plug - Looking at the Transmission, I wan't able to locate a plug in on the drivers side, further research and it looks like it has the TH400 Trans.

[Mrgto68]

I spent a little time under the hood today and have a few questions.



The EGR Solinoid was not connected because the plug on the new harness was different then the old one. The previous harness had three wires where the new Harness has a two wire plug. (see attched photos)
I can easily replace the plugs, but what is the third wire and is it needed?

EGR Solinoid.jpgEGR Solinoid wire colors.jpg


The VSS and TCC plugs were not connected.
I ordered the 2PRS Speed Sensor from JTR. It looks like I have the TH400 Transmission, at this point I'm not really sure what to do with the TCC Plug.
VSS-TCC.jpg

[S.O.B.B.]

The 3 wire egr plug is for evrv.2 wire egr plug is egr solenoid.
Pin A4 says egr.grey wire.
The 3 wire for evrv is the same 2 wires as in the 2 wire egr solenoid plug.the 3rd wire is a ground.hth
1227747--1.jpg
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