Car Randomly Dies, need help on my 4g37 1.8L

[blackfantom]

I've read tons of posts on this and see nothing relating to the 4g37 having this problem, i've read ones about the 420a and 4g37 both turbo and n/a. I've tried a few things regarding the issue, so far nothing works so I will explain my problem and hope someone can be the answer to my issue.

The car 2 days ago started up like crap in the morning, was sputtering and acting like it had water in the gas. Got through that and drove it around for 20 minutes just fine. Later that day went for a 25 minute drive and it went 20 minutes of good driving then randomly decides to cut off at any speed or rpm, doesn't matter. Babied it home with it starting and stopping, letting it cool down for a few minutes and driving it for a few minutes. Car does not overheat but doesn't like to start up right after it cuts off.

Ok first of all, I replaced the ECU with a rebuilt one about 10k miles ago because it would not start when its cold outside, it worked fine until two days ago. I checked the spark plugs and they were really bad, so i replaced them yesterday. Car in general runs better and smoother but still cuts off after warming up. I have a problem with the wiring harness going to the radio, the radio doesn't turn on all the time because of an intermittent wire. Headlights flicker every time i put a turning signal on or hit the breaks, and i think this is related to the random cutting off power to the engine.

I do have a low coolant light on but its a bad sensor and hasn't been a problem, its been on for 10k miles, no CEL's on tho. Im getting spark and fuel pressure to the rail.

However, this is all happening after i ran out of gas and couldn't start it. I filled it up with gas that may be old, possibly 2 stroke gas up to 2 gallons, and yesterday i filled the tank up with fresh gas and the problem with cutting out randomly persists.

 

[scrapy34]

i Have a 91 eagle talon with a 2.0l in it and when i bought the car i had almost the same problem i was getting fuel pressure and spark and everything but if drive around with a fuel pressure gauge on the car so you can watch it i bet you will see the fuel pressure drop 1 or seconds before it dies. i replaced the fuel pump and its been working fine since then so i would check your fuel pump ### sometimes they will slowly die instead of all at once

 

[blackfantom]

i Have a 91 eagle talon with a 2.0l in it and when i bought the car i had almost the same problem i was getting fuel pressure and spark and everything but if drive around with a fuel pressure gauge on the car so you can watch it i bet you will see the fuel pressure drop 1 or seconds before it dies. i replaced the fuel pump and its been working fine since then so i would check your fuel pump ### sometimes they will slowly die instead of all at once

what can i do to actually test the fuel pump? I could see the fuel pump being a slow dying problem because i had a distributer do that in a previous dsm, and i did starve it of fuel and run it low below a quarter of a tank for a while.

 

[DSM1G90]

4G37 motors are so robust, it ain't funny. Owners are known to run almost 400k miles on them before overhaul.

When you swapped ECU's, hope you used the same kind with the same "MD" number.
Usually with the hard starts, I wonder about the ECU situation.

They're quite easy to work on being so small of a block.

What about fuel filter - did you change it out?

Did belt changeouts, per chance?

Good luck-DSM

 

[blackfantom]

4G37 motors are so robust, it ain't funny. Owners are known to run almost 400k miles on them before overhaul.

When you swapped ECU's, hope you used the same kind with the same "MD" number.
Usually with the hard starts, I wonder about the ECU situation.

They're quite easy to work on being so small of a block.

What about fuel filter - did you change it out?

Did belt changeouts, per chance?

Good luck-DSM

I have not changed the fuel filter or belts.

However I have an update. Problem is purely electrical and new symptoms tell why.
I tried cleaning the engine bay to go to a car show within the 20 minutes the car will run. Water on the back hose while the car is on instantly shorted something and it stopped the engine dead. 5 minutes later i got it started and drove it to the car show just fine. Today i tried to start it and there was no power seemingly, then I held it in the start position and it clicked the starter once, no dash lights on what so ever. Turned the key off and back on and instantly started. Drove it around for 15 minutes, didnt die or anything. Parked it, then it wouldnt start at all and made the single starter click.

Again i have a new battery and starter in it that are about a month old, so its not that, its something somewhere in the wiring.

Any guesses of where to start aside from checking every connection and the connections at the ecu?

 

[DSM1G90]

Okey, I think what it could be, but it's a guess: Check the ground wire from the Battery that runs to the chassis. In all due current actuality, current runs from the negative to the positive. Thus, any and all ground connections between battery to chassis needs to be rock tight.

Also, the battery connections ALL needs to be super clean and rock tight. Any corrosion-either by wire or the connector itself-will not produce this "rock hard" connection and will be a weak link in the electrical system.

Good luck - DSM

 

[Stone'S GSX96]

I know that you have a new battery but i would get it tested. I have seen battery's do that and then I would get a in depth alt test because the alt could stop charging when it gets hot.

 

[blackfantom]

I believe I MAY have resolved the problem. I pulled out the radio and disconnected the battery, then reconnected the battery and now the car starts right up as it should every time. Im going to drive it to work today and see if it keeps running the entire time, if it does... problem is resolved.

Turns out the wiring harness between the clips and the radio is spliced and and altered entirely too much which explains the radio problem, Im thinking this might be interfering with the ecu and causing random electrical gremlins.

Stupid previous owner... he had no idea what he was doing and yet he totally screwed up that part of the radios wiring

 

[blackfantom]

problem still persists, it worked right for a day and now its back to the original random shut offs.
could it be a faulty ground somewhere on the car?

 

[tletech69]

hey everyone im bored of 240sx i recently started doing research on dsm and look forward to learning more but does anyone know if a 1.8 n/t
sohc ecu would work and run a 2.0 dohc motor?

 

[blackfantom]

hey everyone im bored of 240sx i recently started doing research on dsm and look forward to learning more but does anyone know if a 1.8 n/t
sohc ecu would work and run a 2.0 dohc motor?

search that, it will most certainly come up on this forum
and I doubt it highly

 

[ThEDrEaMEnDeR]

hey everyone im bored of 240sx i recently started doing research on dsm and look forward to learning more but does anyone know if a 1.8 n/t
sohc ecu would work and run a 2.0 dohc motor?

it apsoluteley will not work on a 2.0 the 4g37,420a,4g63,4g64 are all very different motors



to op have you replaced the plug wires and or distributor?

 

[blackfantom]

it apsoluteley will not work on a 2.0 the 4g37,420a,4g63,4g64 are all very different motors



to op have you replaced the plug wires and or distributor?

plug wires yes, distributor no... and ive had to replace one before on a 94 1.8 that i owned, its acting different than when the distributor went out. With my 94 it would chug along and run like crap and then die, then not start at all till like an hour later. This will run perfect and smooth and then cut off all at once, and then fire back up instantly sometimes, otherwise in a minute or so will fire up.

 

[blackfantom]

I found the problem, its the distributor, car refused to start for 3 days in a row, i got a distributor put it in and it fired right up, however im a couple of teeth off and its running rough.

how can i align the distributor correctly?
put the engine at tdc, but where should the inside of the distributor cap be pointing?
NEED HELP FAST

 

[jjrock5]

The valve timing is a couple of teeth off? If so, you hsve to retime it. Or do you mean the distributor gear is off? If so, then pull the distributor off, rotate the shaft a little in the direction you need to go and slide the distributor where you need and recheck valve and ignition timing.

 

[blackfantom]

The valve timing is a couple of teeth off? If so, you hsve to retime it. Or do you mean the distributor gear is off? If so, then pull the distributor off, rotate the shaft a little in the direction you need to go and slide the distributor where you need and recheck valve and ignition timing.

im a couple teeth off with the distributor gear. I cant find the spot and guess work aint cutting it, i need the ACTUAL correct way of aligning that gear. Pulling the distributor off and rotating the shaft 1 way or the other just isnt working, it refuses to get anywhere near the right spot to where it runs good.

 

[ryguy86eklipse]

I'm not sure how to change the settings on the distributor gear, but this link has TONS and TONS of information as well as mitsubishi shop manuals on almost all of the 4G engines and even some others. Hope you can find an answer in one of them.

Index of /mirage

 

[blackfantom]

I'm not sure how to change the settings on the distributor gear, but this link has TONS and TONS of information as well as mitsubishi shop manuals on almost all of the 4G engines and even some others. Hope you can find an answer in one of them.

Index of /mirage

found out how to do it at work ( i work at honda)

put cylinder 1 at tdc during compression stroke, open up the distributor cap and point it lined up under the plug for cyclinder one, mark the teeth and dont let it move while re-installing the distributor. (this works for basically any distributor too)

 

[DSM1G90]

Done that trick with "dists' all the time: TDC on No. 1 and the rotor point on No.1 Plug wire. - Old Suby motors survived this easy trick as well.

Have to be tricky in knowing how to work the helical gearset for cam and distributor so you know how much offset to rotate so the rotor point comes right below No.1 plug wire.

good luck ...

 

[blackfantom]

Done that trick with "dists' all the time: TDC on No. 1 and the rotor point on No.1 Plug wire. - Old Suby motors survived this easy trick as well.

Have to be tricky in knowing how to work the helical gearset for cam and distributor so you know how much offset to rotate so the rotor point comes right below No.1 plug wire.

good luck ...

yea i took of the cap and watched it rotate and adjusted for it. Car ran perfect for 5 minutes of driving then died and wont start, its getting 0 spark what so ever, so either the junkyard distributor died or maybe a sensor on it died.

Im basically done... anyone wanna buy the car for $400? has a clean title and very clean interior, clutch with 5k mile on it, new battery, new alternator.