1998 4G93 GDI
Hi there! I recently purchased a second hand Pajero IO. Had trouble with engine shudders when stopping. I searched around the internet for solutions and found out about this community of Pajero IO drivers. After following some instructions in the forum, I managed to fix the problem. I decided to join because I would like to keep the Pajero IO for a while as my daily transport, I would try a bit of off roading too when I get better tires.
Why this Pajero IO 1998? For some reason I like the shape/look of older vehicles. Decent fuel economy. 4x4. Reasonable selling price NZD$4500 (just below $5000 budget). Paint and panel still great. Overall it is a good quality car for the price, I believe.
I would like to start here a thread about my Pajero IO to keep a record of the vehicle, including all services and fixes that I will do. Any inputs will be highly appreciated. Cheers!
MITSUBISHI PAJERO IO GDI 1998
Engine: 4G93 1,834cc Petrol Transmission: Automatic
Chasis: H66W-0003971 VIN: 7A8CJ080704003971
Plate: CJP689 Colour: White
Assembly Type: Imported Built-Up Country of Origin: Japan
Start of Ownership: 08-Jul-2015 Odometer: 136,000 Km
Cambelt Changed: 90,000Km
Tyres: 215/70R16
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Service Done: 01-Aug-2015
Odometer: 136,738 Km
Oil: Genuine Mitsubishi Synthetic Lube 3.5L oil viscosity not indicated on the bottle. (free from previous owner)
Oil Filter: Ryco Z411 NZD$10.49
Air Filter: Ryco A1311 NZD$32.16
Throttle Body Cleaned
MAF Sensor Cleaned
ECU Reset
Checked for rust, treated with fish oil
Remarks:
1. Engine shudders when stopping, erratic idle at start up. Fixed by cleaning the throttle body. Remove TB unit from engine, used CRC THROTTLE BODY CLEANER ($18.99). TB had too much gunk.
2. MAF Sensor cleaned. CRC MAF SENSOR CLEANER ($22.99). I believe it is a good time to clean MAF sensor too during air filter change and TB clean-up.
3. ECU reset.
3. Noticed front cross member started to rust when skid plates were removed for oil & oil filter change. Best time to inspect under the engine & under chasis too. Removed rust then treated with Fish Oil ($9.99)
4. Noticed that intake manifold has thick coat of gunk/soot as well, needs to be cleaned soon. Still need info how to do it.
What transmission do you have?
What transmission do you have, and what gear were you in? Did you try downshifting?
I'm a "flat lander" with relatively limited experience on the slopes, so saying 20~30 degree incline, doesn't mean a lot, but, I suspect that is a fairly steep slope. My iO is a 1.8 GDI with an automatic transmission and the only issue I've had on a hill is that it will not downshift by itself, so that it gradually looses speed - what I do is toggle the OD (Over Drive) off button, which forces a downshift to third gear, at which point it will hold what ever speed I was doing.
I should point out here that disabling OD allows the torque converter to lockup in third gear, which manually selecting third does not do - this improves efficiency & fuel economy and reduces heat buildup in the transmission.
If your GDI engine has a heavily sooted intake, it most likely also has a heavy carbon build up on the intake valves, and this reduces the airflow past the valves causing significant power loss - it is a known problem with the early GDI engines. It also affects how the automatic transmission shifts and can cause the vehicle to appear extremely sluggish.
I got an automatic trans
Hi! Thanks for your response. I have an auto trans. I did try O/D off when my vehicle slowed from 80kph to 60kph while driving up the slope. Do you suggest that I should press O/D before I hit the slope to keep it on 80kph (road speed limit)?
Can I just remove the rocker cover to clean the intake valves? Or do I have to remove the whole top end of the engine? I should consider changing spark plugs too, any recommendations?Cheers!
Maybe it's time to remove the plastic engine cover ...
and see what you're really dealing with.
The GDI engine has quite a bit of stuff over the "rocker cover" - to do a proper cleaning job, you will probably need to remove the head - there is supposedly a "walnut shell blasting" procedure that can be done without disassembly if you have a Mitsubishi or Volvo dealer in your area, see if they can do it.
What I did was remove the intake & disassemble and clean it (my car had the two piece cast alloy intake, there is also a one piece moulded plastic one), whilst I had the intake off I also used an engine flush solvent and a bottle brush down the intake
May try a DIY fix first
I had done a DIY engine fix on few different cars already but so far this GDI engine proved to be a bit complicated. Mechanics in this part of the world are expensive though, so I might just try to do it my self. I am still studying the engine schematics and sorting out which parts I need to replace when I remove the rocker cover & perhaps the engine head. A video of similar engine might be helpful but so far I have not seen one yet.
I just want to know how many hours will it take to clean the intake (from removal, dissasembly to refit)?
I would like to tidy-up the engine first, and when it is done I got some mods that I would like to do. NZ seems to be really uptight on modifications, I have to make sure I will get only legal stuff done.
Give yourself a couple of days - there's quite a bit of work -
and that's just to remove the intake.
Get a top overhaul kit or gasket set, and make sure it is the correct one for your engine - there are at least two different kits - remove the top covers and the intake plenum and look at the cam covers, are they linked into a single casting, or are they two separate pieces, and then look at the gasket set, does it have one gasket or two?
If you're going to pull the head, also get a timing belt along with the tensioner & idler pulleys - if you don't know the "change history" of that belt, consider replacing it anyway.
On the GDI engine the intake manifold bolts to the top of the cylinder head and not the side, it then makes a 180* turn and goes down the right side of the block, and then another 180* turn to come back up under the throttle body. The manifold has a couple of bolts underneath that secure it to a support bracket that is bolted to the side of the block - the only way I know to reach these is to get underneath the vehicle - and there are also numerous smaller brackets and braces - you'll also find a couple of coolant hoses under there - from the block to the throttle body plumbing , I'd suggest replacing them whilst you're in there, you can use bulk hose of the correct size - given the work involved to reach them and the cost of the hose, it just does not make sense to leave them.
If I recall correctly, I started on a Thursday & finished up on Sunday - but I was not working on the vehicle for more than 2~3 hours on any given day.
Will consider doing this on a long weekend
I need the car on work days and I only have time to work on it on Sundays. Fortunately, the elderly gentleman whom I bought the vehicle from had the vehicle seviced from a Mitsubishi dealership. The Mitsubishi mechanic assured that the cambelt was replaced few years back at around 90,000kms (they don't keep record of imported vehicles though).
Thank you for your sharing your valuable experience working on a Pajero IO. I will post an update when I get my hands into it. Cheers!
One of the "procedures" I've had reasonable success with ...
has been introducing a "fuel system cleaner" into the intake via a vacuum line.
Research "seafoam" and you find all sorts of stories about people spraying or pouring various cleaners into the intake systems of cars, with varying degrees of success - seafoam may not be available in your neck of the woods, but the procedure can be used with any fuel system cleaner intended to be used by adding to the fuel tank. Cleaners containg PEA (poly ether amines) supposedly work better.
One of the problems with these cleaners and GDI engines is that on a GDI engine the fuel is injected directly into the combustion chamber and so bypasses the intake manifold & valves, and the way around this is to introduce it directly into the intake via a vacuum line - I have used the vacuum line that normally connects to the VSVs for the front axle freewheel mechanism, as this leads into the lower part of the intake manifold well before the air flow splits to the individual cylinder runners.
Syndicate
Max speed 60kph on an inclined state highway?
I did a 100km drive today after service. Power/speed is good on a flat road but I was dissapointed that my Pajero IO can only do 60kph max on an inclined state highway (approx. 20-30 degrees incline). Is there anything I can do to improve it?