I have a 1994 Montero SR with a 3.5L DOHC engine. The original engine threw a timing belt and went ka boom. We swapped one of those "Japanese Origin" engines out of an automobile for the original. I picked this Montero up as a project vehicle, and it has never run since I started working on it.

The new engine, originally set up for a FWD car, had to be stripped completely down to the engine block; and then all the Montero 3.5L running gear was installed on the new engine. After a very laborious (30-40 hours-easy) project, I have no spark to the closest coil pack to the firewall. The engine is missing on those cylinders.

We replaced the coil pack, with no luck. The Igniton Control Module was then replaced, yielding the same results. The crankshaft position sensor and a fuel pump relay were also replaced after reading dash light codes.

I believe the rotor on the crankshaft that works in conjunction with the crankshaft sensor may be out of place. There are three little pins that this rotor sits on behind the belt drive gear, and I'm not sure if the rotor was swapped over correctly. This rotor appears to be uniform in shape, and I didn't see any alignment marks to speak of. Naturally, the Clymer service manual is vague regarding this sensitive area!

My question is: Is this rotor position sensitive, or can it be installed in any direction on its locating pins? Any help would be greatly appreciated!

Ok--the rotor can't be screwed up! It's keyed and only goes on in one direction! Back to the wiring harness!

OK--The wiring harness tests fine between the ICM and Computer and the Crankshaft Position Sensor and the Computer. Timing was also re-checked.

I think the Camshaft Position Sensor may be faulty; but I don't think so! I think the CPS would be an "all or nothing" type of problem; and no cylinders would fire.

I lean towards a possible bad injector telling the system not to spark or the engine computer is bad.

Can anyone share any experiences that may help me narrow this down????

Your help is much appreciated!

Ive done many a swap as this , but the 3.5 DOCH is a plentiful engine in asian parts as unlike the USA. The position of the TDC sensor (crank R) and the crank position sensor (crank L) are very sensitive to bank coil firing.

As i have seen , which yurs may fall into , 91-93.5 3.5 DOCH had 2 crank sensors. a TDC sensor located on the right and a Crank Position Sensor on the left. So the placement of the reluctor ring , behind the crank sprocket had to be done , with care, otherwise , the reluctor pick-up would move in position off of the small roll pins and be off alingment.

As for 94-98 DOCH models had one crank position sensor and a cam position sensor , because it proved to be more conveniant and accurate than the TDC and Crank position sensor both located by the cranks reluctor ring.

Is the 2 cylinders that are missing adjacent of each other , side by side . Or The 2 cylinders that the ignition coil controls?

They are cylinders 5 and 6, which are controlled by the closest coil pack to the firewall. We tested each bank with an "adapter" we made for a timing light.

This particular engine uses one crankshaft position sensor and one camshaft position sensor. The crank sensor has been replaced because of a trouble code, as was the MFI relay under the dash.

I'm wondering if the CAMSHAFT sensor may be faulty, causing an injector not to fire. Then the ECM may tell the affected cylinder (s) no to spark.

Or, a bad injector may be causing the same effect.

I think we're going to pull the upper plenum and ohm test the injectors. I should've done this prior to installation on the new block; but I guess hindsight is 20/20!!!

If those are fine, then we'll do a CPS sensor.

If that does not work, then it's time for an ECM computer!

I'm just wondering what the probability is for each of these "what ifs". If this thing was OBD II, I'd gladly kick for the anylizer and know what's up!!!!

I guess at this point, I've got more time than money. This has snowballed from a "little project" into alot more! People rave about how much they like these things; so I hope to find out!

You've done alot of these, huh! I suppose it gets a little easier every time! This first one has been a real bear trying to figure out all the little "tricks" to get things apart and back together. Take those factors and then add this was a non-running vehicle when I bought it; and that equals alot of time and $$$!

Thanks for your response!

Jason

Ok--

Tonight's fun involved taking a Camshaft Position Sensor off of the Japan car engine and lengthening to fit on the MONTERO. This yielded the same result--shoot!

Then all the MFI connections were tested between the harness anf the ECM computer--all good!

Then I tested the injector harness and ran continuity between all the 6 connections and the common ground. All were 14-something ohms. Right in spec!

The send rotor for the CRANKSHAFT position sensor and the timing were again re-checked! Good on both counts.

I still have no spark from the back coil pack to cylinders 5 and 6.

This leaves us with the ECM computer...

Its a weird thing . As yu see teh firing order is 1-2-3-4-5-6 , and starts bank back of firing to aft.As i have seen which in particular in this case is that as 91-93.5 DOCH we have are similar to teh 1994 onlee model in the USA which should have used 2 crank sensors. a TDC and a crank position.

But in yur case yu may in ways just have 2 dead injectors or they are not working.On teh year yu have the fuel injection is MPFI onlee 96.5-98 3.5 DOCH domestic asian models got SFI(sequintial) In a MPFI the injectors are always pulsed and the spray is varied. In a Sequintial , the fuel injectors pulse in a order command oppossed to teh firing order.

So there may be an issue with "dead" injectors

I've sifted over this site for about 2 hr. looking for clues to my mystery.

Every post I looked at gets to this point, and then....

...What happens?????????????????????????????????????????????????????????

Do people just throw their car/truck Montero away?

I do solemnly swear to you, the people of mitsubishi-forums.com; I will tell you the outcome of this debacle!!!!

Your help is appreciated!

:57:

Kit, Thank you for your help and insight! I have seen in my searches that you have been very helpful to many people on this message board!

I tested the injectors through the wiring harness, but I might either pull the upper plenum or check the dead cylinders for fuel evidence after running the motor for a while.

Do you think the ECM computer could be the problem? Would you check the injectors first?

Thanks again!

Jason

Its very hard to accuratlly test it that way.

The way they work is that the fuel injectors are fed an power source ignition on . And then the ECM feds a ground signal to the injectors, It varies the amount of ground signal to the fuel injector to vary the spray of the injector. Or per say at idle , the grounding signal that is sent to teh injectors frum the ECM will be a weak signal and the signal increases by throttle input, AFM and ecm command as needed to match the air ratio.

Its hard to say that the ecm would be the issue , cutting out 2 cylinders. The left bank the engine are 1-3-5 and the right bank is 2-4-6. ECM issues on these models usually would cause starting issues that i have seen. (no spark reference) type of cases. usually ECM that have faults cause performance issues , and ignition systems issues as in intermitten starting . I have not really seen any that have caused closed loop issues to fuel injectors. If yu have a Multimeter , yu can check the continuity at the injector. And also the "power ground" frum the ecm.

Hello, Kit!

I will pull the plenum off and test the injectors.

Thanks!

I cant wait for thunder to get this running. Good luck.

My Mitsubishi Triton PLUS was originally a SOCH heads on the 3.5 as well as my Diamante VR-S , but being both are AWD i needed more power , and i opted for DOCH MIVEC heads of of a 94 for my Triton and 96 DOCH MIVEC heads off of 2 Mitsubishi GTO's The 3.0 and 3.5 DOCH heads are the same. Now i run both High compression DOCH 3.5 on both vehicles. Hope yu get yur issue sorted with the 2 cylinders.

All six injectors spray fuel!!!!

Several sprayed "less fuel" by my catching method, but they all get fuel and spray!!!

I am repalcing the #3, #5 and #6 fuel injectors because there's some junk in the ports and spray less fuel than the others over a few cranks.

Still no spark to cylinders 5 & 6...

How 'bout blaming the ECM computer at this point!

Any takers????

Thanks!

Okies i was slightlly confused by yur explaining atone point. So the main coil itself is not firing at all. Is it getting a referance signal in? There are one thing yu can look at , the ignition "power unit" or basically the control module. It helps referancing of the ignition coils via the ECM to correspond with correct cylinder firing. It basically powers the coils , via referance of the ECM. It can caut out an ignition coils performance or total operation of it.

An ECM as i had stated i believe here , can also cause ignition issues. usually no firing/starting situations.

Hello, Kit!

I have a new ICM (Ignition Control Module) installed.

I just took apart my ECM and see no signs of burning on the circuit board or bad diodes...

I don't know, though. It's possible still the ECM computer is faulty!

This has to get fixed sooner or later!

Thanks!