TBI # 17087101 vs 17093030

[wheels87k5]

When I bought my 87 blazer it came with TBI #17093030. Decoded it means it came from a 1993 vehicle, Monojet (1bbl), with auto tranny? This TBI unit has 2 injectors....doesn't that mean it's 2 bbl? Or did I lose another marble!

I found a used TBI 17087101 on ebay that came off a 1987 K5 but with manual tranny. And I have been using it since then. Only now it surges because of bad bushings on the shaft so instead of rebuilding it I swapped the 1993 TBI unit back in. It runs good but the idle is a little low. Is there an adjustment for this?

What is the difference between the two? Will my 87 K5 run without any problems using the 1993 unit? Is there any adjustments I need to make. Will it make the blazer run richer or leaner?

Just want to make sure before I get too far and for some reason the ECM takes a dump because of the different TBI.

willie

 

[airemdwn]

At the minimum the TPS Throttle position sensors are different and i believe some vac lines and throttle shaft plate differ from some models? The 93 should have a small round connector while the 87 should have the large flat connector. I didnt think you could swap the sensors,just change the plug i suppose.

Depending on what the TBI came from, Fuel pressure may be different seems like Trucks tended to run a liitle lower psi.But thats easy enuff to fix with a little research.

Look at http://www.tbichips.com/ if your looking to start to upgrade. so you dont waste time and money.

 

[wheels87k5]

Yep...I did have to wire the different TPS for that year but it seems to work.

It does have an Adjustable Fuel Pressure Regulator. I'm going to set the IAC and see if that brings idle up a little. That's pretty much all that I am after right now.

I'm thinking about getting the cfm-tech TBI unit instead of rebuilding the other one.

Does anyone on here use the cfm-tech TBI units?

willie

 

[British Slave]

Idle Adjustment


Take the paper clip and open it up and form it into a big "U" shape. Insert the clip ends into the ALDL in the 'A' and 'B' pins.
Turn on the ignition, but don't start the engine. Wait 30 seconds. Now, go remove the connector from the IAC. Remove the paper clip.
Start engine. You are now going to adjust "minimum air". There is a Torx screw on the side of the throttle body. This is what needs to be turned to adjust minimum air, or more commonly known as "idle speed". It comes from the factory with a protective metal cap over it. If the cap is still there, use a small punch to knock it out. Set the idle speed to 450 rpm, rotating the Torx screw clockwise to raise rpm, and counter-clockwise to lower rpm. Once the idle rpm is set, turn off the engine.
Re-connect the connector onto the IAC. Start engine. Idle speed is now once again governed by the ECM, but your idle should be smooth and steady, approximately 600 rpm in Drive (for unmodified cars).
If you set an SES light by having the IAC disconnected, then after shutting down the engine disconnect the negative battery terminal. Wait 5 minutes. This will clear the ECM of all trouble codes. Re-connect the battery and drive the car for 20 minutes to allow the ECM to relearn your driving style.

 

[wheels87k5]

Besides wiring the TPS for this (1993)throttle body, the TPS voltage is different than it is for the 1987 TBI unit.

When setting minimum air for the IAC, you can't pull the TPS voltage down to .50 volts which is supposed to be ideal for the 1987. Motor wont run....but it does run at .85 volts where it is set for the 1993 unit.

Doesn't seem to bother the ECM or engine performance. But I'll either rebuild the 1987 unit or get a new one from cfm-tech.

willie