1987 Colt Vista problems

[420ADaily]

So i picked up this 87 Colt Vista 4x4 for 1k, really nice inside and almost flawless on the outside. Problem is, after a month of so of driving it, it shut down on me going about 45 mph (no hesitation, no spudder no nothing, just stopped) and after i tried to start it again, it seemed like all compression was lost and it was just spinning.

I've heard of things on the Colt that could of been the problem (fuel pump, ignition, ect.) and I thought the timing belt might of broken or slipped, timing belt is intact BUT it may have slipped. Currently have the engine torn down and have been trying to see what it is.

Any help would be GREATLY appreciated.

 

[DSM1G90]

1987 - Bet the timing belt slipped since you noticed compression was lost and was just spinning.

Too bad you didn't check that out first before the tear down.

You didn't mentioned the miles posted on the odo, but bet it's well over 200K with a 27yr old vehicle.

Thing contained the SOHC 4G63, which was a non-interference motor.

 

[420ADaily]

The car has 77,683 original miles, ive started to put the engine back together today and im about 3/4 finished but i do have a timing belt on hand. in the engine compartment it has it stamped Engine:G63B. Is the G63B the SOHC 4g63? also, to get it back on the road, what do you recommend doing?

 

[DSM1G90]

Same motor just that Mitz back then didn't use the cylinder number for the first character in the number string - like the large G55B (2600cc) was a 4G55B motor.

If I remember, the "B" was a code for a carburetor motor.

Just put it back together the same way you tore it apart - carefully and pay attention on what you are doing.

77K miles on a 27year old belt. Bet that belt was plenty dry and the teeth had all but hardened up.

 

[mitsubishikid]

No the B meant it had the jet valves in the cylinder head, my motor in my 87 Vista is the G63B too and mine is equipped with multi point fuel injection, the 1987 was the first year the Vista was available with MPI.

Some later 1st gen Vistas made during the end 1988-1989, had the 4G63 SOHC but I noticed they did not have the jet valves in the head, but any G63B motor I ever saw [that had it's OEM head on it] had the jet valves in the head.

Is your Vista MPI, or carburetor equipped?
Did you do a compression test before you tore it down?
I have the FSM for the 1987 Vista so if you need any info let me know.

And the G63B SOHC motor is not an interference design so you couldn't have bent any valves.
Did you check the MPI relay its under the dash on the passenger side. Disconnect the battery if you do inspect it you don't want to melt the main harness down.

 

[420ADaily]

Greatly appreciated, thank you!

It is MPI, no carb. I did not do a compression test before I tore it down, it was kind of a "in the moment" choice.

So if I check the MPI relay, what should i look for/expect to see?

 

[mitsubishikid]

if it looks like there is burn marks on it, it should be suspect, but you really should use an ohm meter to test it properly.

here's a good pdf I found on the net on how to test the relay google this and it should show up.

manual.pajero4x4.ru/?wpfb_dl=9029

follow the directions for the 2.4 Mitsubishi relay.

some guys use their ear, if it does not click at all when the key is in the on position it is bad or wires that supply it power are shorted out cut or maybe fuses are blown...

Another thing that would be helpful is, what are the symptoms of your diagnosis...
did you check for spark or fuel when the car killed, cause it could also be a bad I.C.M, a bad coil, or even a bad wire connector on any under hood sensors or leaking caps inside the e.c.u unit.

here is a better link

 

[420ADaily]

Ill test it today, when the car died i did check for spark but not fuel and it was getting spark. Ive checked all wires in the engine compartment and none are chewed or show signs of wear.

 

[DSM1G90]

Then, that explains why a few years ago, I had a 1.8L Eclipse that needed another motor.

Went to a JDM place that got one and he installed it. One valve was ticking a bit and I though that I might have had a bad lifter and was planning on doing lifters on this head.

Took the cover off and behold, I had adjustable rockers with the MCAJet third valve, and the No.3 EXH was way out of specs.

I used the 4G32B cold specs to get that valve adjusted, along with the other valves, and the motor ran quiet ever since-and it has tonnage of pep for a 4G37 where I had power even with the speedo past 120mph and the tach close to 6K.

 

[mitsubishikid]

yeah gotta love those MCA jet valves, they have even helped me barely get past smog inspection one time,
[they help with the low speed emissions.]

yeah the only thing I hate about them is some of the USDM jet valve equipped heads I noticed had a weak spot in. IIRC cylinder #3 and the heads would crack there in between valves

I've yet to see this issue on the SOHC 4G63 but I think it has something to do with the fact that it had no jet valves, I guess they saw the issue but decided to quietly sweep it under the carpet. A no fuel condition could be, the MPI relay, the fuel pump, the ECU, the fuel filter could be clogged.

if your Vista has the injector resistor pack that could also be bad [it would be located on the driver side strut tower] it looks just like a DSM one, even has the same connector.

and did you test the fuel pump directly to see if it would work when voltage is directly applied?

 

[420ADaily]

i checked the fuel pump the day after it happened, it was working fine. but one thing..before it quit it would REALLY have trouble starting (would try for a while then start on the 3rd-4th try)i have taken a picture of it that will be under this of the engine as it sits right now.

 

[mitsubishikid]

So the engine rotates but will not start.

Disable the ignition coil [by unplugging it's power connector] remove the spark plugs, and if you can smell fuel in the cylinders after cranking it once or twice it could be a timing issue, maybe a bad distributor inside the distributor on the Vistas is the TDC sensor and the crank position sensor are built into one unit, maybe one of them has gone bad and is causing the car to not fire at the right time.

If you don't smell fuel after cranking maybe the injector resister pack is faulty, and not supplying the injectors with power could also be the ECU in this case too.

A bad alternator can also cause a car to kill all of a sudden but it's less likely, but still it's worth investigating.

It could also be a bad or partially bad power transistor AKA Ignition control module or ICM, it's worth it to test that too. It's on the bracket in the picture you posted, it looks like this http://www.rockauto.com/catalog/raf...ck[PHP_SESSION_ID]=u30nsksn9beo619k4jlt0ut641. They can cause issues like rough starting if the connectors are loose or damaged or if it's corroded on the inside of the connector.

BTW sorry I posted the wrong PDF link in that earlier post for testing the MPI relay, here's the right one.

 

[420ADaily]

Ill try everything tomorrow, and i dont think it could be an alternator because it was brand new when i bought it. My friend also said it could be an ECU, so ill check that tomorrow too.

 

[420ADaily]

It is up and running! Thank you guys so much!

 

[mitsubishikid]

Your welcome man. I'm kinda curious to know what turned out being the issue?

Other Vista owners are likely gleaming info from this post as we speak, and it might help them out to know.

 

[420ADaily]

This was the culprit, cam took 15 teeth off the belt.