Trying to Survive - '92 Suzuki Jimny Ownership Log

[pwuser162557941033]

Yes sir! That's why I chose it. The closest I get to being on a dirt rally is when I can easily overtake a riced-up Civic/Sportage/Grandie crowd on the dug up terrain all over Karachi, without having to slow down and pull my trouser legs up like them.

And interesting - do you think OX being pulled to 0V/5V/12V tells the ECU that? I have had the cat light on on my dashboard forever. Can probe the OX pin on the harness and see if showing it GND or whatever voltage it wants will make a difference.

[Xulfiqar]

Try simulating it, i think its a basic 12v line. I dont know for sure as one my memory is fading on those oldies and two, suzuki may used something different.

Btw, Ive had the fortune of taking a delta integrale (fat fender) on a twisty mountainside.

Its very strange، not very comfy, lags for eternity, but the way that car applies power and the chassis handles is something I dont have words for. Its very raw and very italian.. you keep smiling as you drive it.

[pwuser162557941033]

Will do. I wonder what temperature the OX fuse triggers at, it is a good safety feature when running high boost that I have no fuel table for. It's a one wire fuse, so it probably breaks and leaves the circuit open instead of in contact with GND. That's what I think is happening.

Btw, Ive had the fortune of taking a delta integrale (fat fender) on a twisty mountainside.

Its very strange، not very comfy, lags for eternity, but the way that car applies power and the chassis handles is something I dont have words for. Its very raw and very italian.. you keep smiling as you drive it.

That's fantastic! What an opportunity.

[pwuser162557941033]

I think it's of note that the service manual doesn't even make any mention of the cat light. On my gauge cluster, it's just to the left of the turbo indicator lamp.

This manual is probably for a Type 1 JA11, or a Type 2 before the emissions equipment was revamped to include it.

Yeah, it's not here either.

The four blank pins on the ECU in the manual, to the right of the VCC and PM pins are:

MON STA
PSS DR
VCC PM

Wonder what they do. PSS is probably for power steering pump.

[Xulfiqar]

VCC is referennce and PM is map
Sta is startup signal mode.
PSS is usually power steering switch
MON is plausible chance of monitor as exhaust temp monitor maybe

[mumtazkhan525]

Send me Pictures Please

[pwuser162557941033]

Why

"I (Muhammad Mumtaz) am an SEO expert at Mechtechnologies serving for 8 years showing up great results for search engine optimization."

How are you an SEO expert if you're spamming links on a publicly accessible forum?

[pwuser162557941033]

Removed the oil temperature gauge from above the gauge cluster because of poor visibility in daylight. Moved the thermocouple to the boost controller box and added oil temp readout and control logic. Thankfully the OLED display has much better contrast and daytime visibility.

It only allows full duty cycle output for max boost when the oil temperature is > 90°C. Gradually adds duty cycle in 10°C increments starting at 60°C.

[pwuser162557941033]

i think its a basic 12v line

It's 12V. The connector near the cat was covered in road grime. Sprayed it with WD-40, then grounded it with the braided steel wire that was coming off the thermal fuse.

It sinks 35mA to ground, and the cat warning light turns off on the dash once the engine is running.

Let's see what effect it has on performance and fuel trim.

Update: Didn't notice anything apart from the boost level being higher on average, suggesting that yes, the ECU might have been trimming back fueling. I had to reduce the duty cycle from 15% to 13% to maintain the same amount of boost. Apparently the ECU aims for an AFR of 11.5 "for optimal turbocharger performance."

[pwuser162557941033]

The actual boost curve.

[pwuser162557941033]

Some more screens from the final prototype that I'm quite satisfied with. Controls everything automatically.

I no longer have to ever exceed 3500rpm in any gear when driving around the city. The engine has plenty of torque because of the faster spool, now showing the stock boost indicator light as early as 1500rpm.

Oil seems healthy, doesn't need a change for a while. It does need just about 250mL more, because the turbo drain hose deteriorated due to the heat in that area such that it kinked and the turbo started billowing smoke out the exhaust again. Trimmed the hose to remove the kink, no more smoke. You can't just replace it with a section of any old hose - the turbo drain hose must be able to withstand the intense temperatures in that area as well as the very hot oil flowing through it. I'll order the appropriate hose for later.

For anyone interested, the hose has part number 13946-81050, the two spring clamps are 09401-20406. Length is 175mm, 15.9mm ID x 22.9mm OD, temperature rating 125°C.

It drank almost a litre of coolant from the overflow reservoir, and that had me worried, so I'm keeping an eye on it. No indication of a leak or any other cooling system performance problems.

Every other parameter that I can monitor is completely normal. Oil pressure is 80 - 120 kPa at hot 1000rpm idle. Coolant and oil temp and pressure are normal. Battery voltage is normal. Boost absolute maximum is 100 kPa when oil is hot.

Onwards.

[the_mira_guy_08]

This thing needs a better headgasket. My mira runs fine but if my leaky headgasket isnt fixed then i'll probably looking at a new engine.

[Xulfiqar]

You need to add a heat sleeve for the turbo drain line.

[Xulfiqar]

This is very very very nice…

[pwuser162557941033]

Thank you very much, I appreciate it. I've tried to lay pertinent information out as cleanly as possible. The bar at the bottom works like a vacuum gauge, extending into the left for vacuum up to -55 kPa and into the right for boost up to 100 kPa.

I added more precision in the duty adjustment and the oil temperature compensation factor (in the top right) is now dynamically applied per degree of sump temperature below my 85°C threshold.

You need to add a heat sleeve for the turbo drain line.

Really? I managed to find some high pressure, high temp, oil rated hoses online that I could buy, and I think even an AN12 braided hose would fit those dimensions.

[Xulfiqar]

Yes that will work too, but I rather follow best practice, in mercedes HD trucks (with the turbocharged diesel ohv v8) the turbo drain line is covered with a heat sleeve.

Trucks such as Mercedes tractor head has a lot of money riding on its performance, cannot afford downtime for silly things like a hose, so its protected from the factory!

[pwuser162557941033]

Yes that stupid hose has been the bane of my existence, especially if it ever acts up after an overnight cooling cycle on cold start first thing in the morning. Apparently, there is a hose market at Saeed Manzil, but they, too, need saampils.

So like a glass fiber wrap thing, the kind of thing used on exhausts?

I bought some heat shielding that had a glass fiber inner surface, and a reflective silver exterior, to wrap around my AC lines that pass near the exhaust. Would that work?

[Xulfiqar]

Yes sir

That silver looking sleeve the same material you want, such material is sold in the paan mandi market and also bohrapir, its usually sold by merchants who deal in boiler parts.

I used to buy it in meter lengths and it comes in multiple sizes too, some are sold with velcro type fasteners and some are sold as flat fabric which you tie with wire.

Remember its supposed to be loose fitting.

[pwuser162557941033]

Summer has been taking its toll.

This is where I've been losing coolant. Will replace this with a PTFE hose with a braided steel jacket. Anything near the turbo or exhaust manifold disintegrates pretty quickly.

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Also, a night ago, I could hear gas rushing out of the discharge line from the compressor when I parked the car. Overnight, the system was completely emptied of refrigerant.

Got a new discharge line and some refrigerant. No vacuum, no nitrogen, but pressure tested with "air" using a "fridge ka compressor" up to 250psi. Andaazan meter readings, no numbers actually checked or verified. Return line held with hand by AC guy to verify "cooling" and "gas puri hogayee hay."

AC blowing "cool-ish" again. Slightly better at idle than it was before.

@Xulfiqar I've loosely wrapped the line to the evaporator from the dryer, that passes by the exhaust, in the silver velcro thermal insulating wrap.

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Measuring AC Performance
Stationary Idle, Blower Speed 2/3, Recirc, Doors and Windows Closed.

Allowed ambient temperature to stabilize before test began.

Sensor placed on driver's side headrest.

Vent temperature is 16.6°C at idle RPM. Not great, but much better than ever.

[pwuser162557941033]

Top scientists scheduled an impromptu private viewing of the Jimny. They concluded all was well.