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2008 Lancer sportback throttle lag + hard to accelerate

11K views 19 replies 5 participants last post by  KiT TeUnG 2549 
#1 ·
Hi,

I am new here, so I would like to say hi to everyone.

I looked through the forum for a similar issue, but I couldn't find anything. Probably cause I didn't search correctly, but I am not sure what the right keywords are.

Anyway, I recently bought a 2008 sportback lancer, 1.8, 140hp and runs on gasoline. I have 2 issues which may be related, if not, let me know and I will create a second thread for the second issue.

So the first one is a lag in the throttle, but only in the low RPMs. When I get the car to around 3000 RPMs the throttle response seems fine. Interestingly, when the car is in low RPMs, the first half of the throttle is not responsive. What I mean is that I have to press the pedal to the half way point of its available movement to get any response. Maybe this is true for the high RPMs as well but I cannot feel it. I've changed the spark plugs, but to no effect :(

The second issue is that the car really struggles to accelerate in fourth and fifth gear. Also when I almost rev it on first gear and then shift to second, it loses power and accelerates somewhat poorly. While in full throttle and accelerating, I am hearing a loud noise from the engine, like it is sucking a lot of air, but it almost feels like the car is slowing down instead of accelerating. Idk if this is normal, maybe it's because of the smaller engine.

One more thing to note is that I bought the car with LPG installed. It runs absolutely the same on gas and LPG, though, so I am not sure if this may be the issue.

Any help would be appreciated, thanks :)
 
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#5 ·
I will be changing oils and the oil filter next week, the air filter looks very clean though, so I am wondering if it is worth changing it. Regarding the MAF I will try to clean it tonight. Regarding the OBD II codes - I have to buy a reader...Will the bluetooth ones do the job?

I will also have to check whether the pedal is electronic as I have no idea currently.

Thanks for now, I will post another reply when I have more information.
 
#7 ·
Sure, thanks :)

Weather is really bad here, so I will not be doing any work on the car today, but I checked the OBD codes. There are 3 present, 2 of them seem to be permanent, they are for the O2 sensor and the catalytic converter. The guys from the repair shop told me these are because of the LPG and because there is no catalytic converter :grin2: But there is a third code now - P1021. I looked it up and it looks like one of the injectors is bad. Is it a good idea to change them all? I also plan on re-installing a catalytic converter. Do you think this may have a positive effect? I will leave the O2 sensor for last in case its faulty codes are generated because of the lack of a catalytic converter.
 
#8 · (Edited)
I can only guess that the previous owner got rid of Cat etc. to run fine on LPG.
I would guess it runs kind of in a predefined setup because of missing info from Oxygen sensor.
Meaning fixed ignition at any rpm (regardless of knock sensor)
Meaning fixed amount of injection (regardless of O2 sensor)
etc. etc.
I get the feeling the car was tuned to LPG -
if you want to run on gasoline I would guess you will have to put it back to factory state ...

P1021 MITSUBISHI - Engine Oil Control Valve Circuit Bank 1

Possible causes
- Engine oil control valve circuit is open or shorted
- Engine oil control valve poor electrical connection
- Faulty engine oil control valve
 
#10 · (Edited)
Is the P1021 something to worry about?

it is if its a mirvic motor

P1021 MITSUBISHI - Engine Oil Control Valve Circuit Bank 1

Possible causes
- Engine oil control valve circuit is open or shorted
- Engine oil control valve poor electrical connection
- Faulty engine oil control valve
 
#13 ·
Thanks,

I have not had time to do any work on the car yet, besides cleaning the MAF, which did not seem to have any effect. The sensor was clean anyways. I will check the valve and the throttle body during the weekend. Last night I cleared the logged fault codes while the car was warmed up, then I took her for a ride and the P1021 error did not come up. Is it possible that the oil has lost its properties and gets really thick when it is cooled, so the valve cannot move properly because of the thicker oil? I am gonna be changing it next week anyways, just wondering if this is a possibility.
 
#15 ·
I would say yes - oil looses it´s properties with mileage.
It also accumulates dirt (exhaust fumes - half burnt carbon etc.)
Dust that got past the air filter - yes - it happens.
The additives in the oil are also meant for this - they encapsulate the dirt.
Protects the engine - but there is only so much ....
 
#16 ·
Hi everyone and sorry for the delayed update, I was pretty busy the last week.

So I changed the oils and all filters and also found what's causing the P1021 error. It was a faulty wire which had to be replaced. The LPG system is now disconnected, and the car runs without logging any errors, but it is still sluggish. A guy who used to have the same car told me that it is sluggish by default, but the issue can be fixed by installing a turbo :D I may simply do this in a couple of months or so :D I am yet to try the car in high speeds, though, so I don't know if that issue has been fixed by fixing the valve wire.
 
#17 ·
North America doesn't get the same engine options that arrive globally. Our lancers have the 2.0L and the 2.4L and I wouldn't buy the 2.0L and wasn't even blown away by the 2.4L feeling slower than my Outty. I don't know if they make them for the 1.8L but the under drive pulley I installed on the Outty made negligibly gains of actual power output etc but a very noticeable difference in throttle response. If you can find a pulley for that motor might be worth trying.

If you will never use the LPG system again might also want to tear it out, the tank etc adds some unneeded weight. LPG vehicles are another thing we don't see anymore except for the occasional 80's pickup that is half rusted and ready to fall apart. Just never caught on over here. Banned from too many parking structures etc. Forklifts are pretty much the only thing commonly run on LPG.
 
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#18 ·
Actually like stated above , on this care and engine size LPG adds no benifit. It actually hinders the car ALOT. The engine size is small and very efficient factory wise , LPG system adds roughly 227 kg of weight to the stock weight if not a little more. That 1.8 (4B10) is same in design as the 2.0 (4B11) and 2.4 (4B12) just a smaller size which is supposed to me more fuel efficient. LPG doesnt benefit any small vehicle with 4 cyl, especially a small 4 cyl . Unlike our larger Taxi in Brasil and mainly Thailand which 6 cyl engine (Toyota Comfort) which is a large taxi with LPG or some of out midsize lorry .

This MIVEC system is nearly continuous as opposed to the staged older system. If the oil control (variable timing solenoid ) is stuck open , it will keep high pressure and the intake camshaft improperly advanced , hindering low end power and acceleration. Also i definite is spark plug replacement after fixing the issue
 
#19 ·
Thanks, I will definitely look for a pulley kit. As for the LPG - it is currently detached, so I am driving on gas only. I will drive it like this for a month to see how it is.

I am from Europe and the gas prices here are a bit higher, which is why a lot of people use LPG. Especially in my country where the price of the gas is like double compared to the US. We pay ~4.5 USD per gallon :( (On the contrary we pay almost nothing for fast internet :p)

Note: The spark plugs are 2 weeks old, should I change them again?
 
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