1993 2.6 Amigo Engine Wiring Diagrams

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1993 2.6 Amigo Engine Wiring Diagrams

Postby The_Amigo » Sun Feb 21, 2021 4:27 pm

Looking for some good wiring diagrams for a 1993 2.6 Amigo

I have a Haynes manual, but I'm finding the wiring diagrams are more for the older 2.6 MPFI.

The main things I"m looking for
The MAP sensor location and wiring.
Does the ECM get camshaft information from the distributor?

What I'm working on here is a incomplete project. The guy I got it from rebuilt the engine, but never got it to run well. Rough idle, misfires and stumbles when revving up.

Compression, leak-down and timing all good. Found some vacuum leaks (cracked lines). EGR has been removed and blocked off.
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Re: 1993 2.6 Amigo Engine Wiring Diagrams

Postby Ed Mc. » Mon Feb 22, 2021 4:56 am

The '93 2.6 has a MAF (Mass AirFlow) sensor, not a MAP. It's located downstream and integral to the air filter housing, at the driver's front corner of the engine compt. AFAIK the distributor is the only source of rotation signal to the ECM, there are no cam and crankshaft sensors on this engine.

Check your cam timing. You can pull the upper timing cover and check to see if the mark on the cam belt sprocket aligns with the stationary mark when #4 cylinder (not #1) is at TDC, on its compression stroke.

Be aware that the harmonic balancers on these are notorious for slipping (the rubber bond between the inner part and the outer ring breaks) and then the timing mark on the balancer won't line up with TDC. So be suspicious of that if things don't line up right.

If things seem off, there are 2 ways to determine TDC for belt alignment purpose: use a timing stop or dial indicator thru the spark plug hole, or pull the harmonic balancer & lower timing cover, then use the alignment mark on the crankshaft pulley, which lines up with a stationary mark on a cover at the front of the block.

Make sure your firing order is correct, and the dist. rotor is pointing at the correct cylinder to be sparked. You can do this with either #4 or #1 cylinder (both are at the top at the same time). Whatever cylinder you reference off of (1 or 4) must be at TDC compression stroke.

It's not uncommon to see clogged injectors on these, too. You may be able to isolate your problem cylinder(s) by doing ignition or injector "drop" testing. i.e., pull a plug wire and see how much it changes idling. Same idea, disconnect an injector electrical plug and see how it behaves.

If the particular cylinder where you unplug an injector or pull a plug wire doesn't make much difference in idle quality, that cylinder isn't pulling its load and has some sort of issue.

This is an extremely informative thread on cam timing and ign timing adjustments, unfortunately due to the Photobucket fiasco in the past, the pictures are no longer viewable. Still a lot of great info if you can follow along:

https://www.planetisuzoo.com/viewtopic.php?t=60015

BTW, if you haven't adjusted the valves, do so. A couple of tight exhaust valves can mess things up, and these engines are notorious for burning valves when adjustments haven't been tended to. At least yours has good compression!

Last thought, check both the rubber and plastic air intake tubes for leaks. This problem has come up in a few recent threads, folks have found massive air leaks in the hidden areas underneath. That'll really mess up the engine management!!

HTH & let us know what you find..........ed

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Re: 1993 2.6 Amigo Engine Wiring Diagrams

Postby Buster28 » Mon Feb 22, 2021 6:23 am

The Engine Control Module (ECM) has two electrical connectors, one is 26 Pin and the other is 22 Pin
The MAF power (Pin 2) connects to the 22 Pin ECM connector Pin 14 (RED)
The MAF signal (Pin 4) connects to the 22 Pin ECM connector Pin 21 (WHITE)
The MAF ground (Pin 3) connects to the 22 Pin ECM connector Pin 19 (BLACK)
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Re: 1993 2.6 Amigo Engine Wiring Diagrams

Postby The_Amigo » Mon Feb 22, 2021 4:42 pm

All my other vehicles have both a MAP and MAF sensors. That was throwing me off. Had a closer look at the MAF sensor. He said he replaced it with a new one. Its the wrong one. Its for the 1st gen I-TEC. Its noticeably smaller. Mine does have the 2nd gen I-TEC single blade round throttle body, not the two blade oval.

Can you confirm the arrow on the MAF points towards the air filter, not the direction of flow.
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Re: 1993 2.6 Amigo Engine Wiring Diagrams

Postby Ed Mc. » Mon Feb 22, 2021 6:31 pm

The_Amigo wrote:All my other vehicles have both a MAP and MAF sensors. That was throwing me off. Had a closer look at the MAF sensor. He said he replaced it with a new one. Its the wrong one. Its for the 1st gen I-TEC. Its noticeably smaller. Mine does have the 2nd gen I-TEC single blade round throttle body, not the two blade oval.

Can you confirm the arrow on the MAF points towards the air filter, not the direction of flow.


It would seem the arrow on the electrical sensor points to the air cleaner. IDK why, that's just the way they did it. See the attached pic.

The MAF flange bolts to the air cleaner housing. See that hole in the pic I posted? That's where the sample of airflow goes into the MAF "hot wire" sensor so it can do its thing. I've attached a pic of the downstream side of the MAF as well. It shows the rounded body for the rubber air intake tube/boot.

So with the MAF body mounted in the vehicle, the sensor connector ends up pointing inwards.

I'd imagine that having the wrong-size MAF would really mess things up! That complete assembly is quite expensive (over $470 plus shipping at Rockauto), so your best bet is a Pick-and-Pull or other wrecking yard. Check on http://www.car-part.com and you might find a used MAF in your area at a reasonable price.

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