help diagnosing engine problem, 2L N/A.

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RicKii``

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ok so i'll keep it simple and put it in point form, if anyone can help me in what to do next:

got new motor put into my CB lancer, its a G4CP from hyundai sonata. similar to the 4g63 NA if not the same.
previous owner had the timing belt changed and misaligned it by 2 teeth so she vibrates like hell on idle. But still drove fine.
We fixed that up, and she was alot better with more power.
But on start up while trying to crank over, she cranks over, maybe twice then it felt stuck. have to try 3 times and then it'll "latch" on and start.
Now, while driving, very noise tappet sound came from the motor. The power also dropped, the engine got more lumpy, kind of like the sound of misfire. I would be cruising at 60 and once i took my foot off the pedal, it'll be kinda "jumpy". the engine would feel like its jumping. It also would hunt idle at the lights.
The tappet like sound got louder and louder so i panicked and stopped the car.
Tried to start it over after 15mins, it would crank over but not start, just sit there cranking.
If you gave it some gas, it'll crank and sound like it'll start, very noisy "clack clack" sound from the engine but then it would just stall once you got off the gas.

Does anyone have any pointers to what i should check? we only just put the motor in so Im quite depressed now that the motor isnt running.
thanks guys
 
first up is a compression test. this will check for internal damage. get a screwin one cause then you can do it yourself and the pushin one wont reach the plug hole. like this:
http://www.ebay.com.au/itm/CP7827-COMPRESSION-TESTER-KIT-Made-USA-/280742805888?pt=Motors_Automotive_Tools&hash=item415d934180
available at repco or auto one or whatever you have.
do a dry test and then teaspoon of oil in the cylinder for a wet test. post results for diagnosis and next stage

this conversion would have had plenty of grunt, did you use the sonata ecu?
i have sonata g4cp sitting in shed for next engine
 
thanks for the reply, i managed to get a compression tester off a mate.
180 - 165 - 175 - 0(zero)

GG.

next stage would be?

yes, we used sonata everything, it had plenty of grunt and alot more zippy than a suzuki GTi.
definately a worthy upgrade if all 4 cyl are working.
 
well it safe to say that the head needs to come off as something is hurt inside. what did the wet test show? if the wet test is much higher, you might as well do the rings. if not then they prob ok.
if you can get compressed air into cylinder that has 0 then that will tell you where leak is before head comes off.
but because it is 0 it will be fairly obvious when head is lifted.
you have 10% variation other than 0 so prob not too bad. when you have rocker cover off, you may be able to see some of the valves are stuck down slightly. anyway, pull the head, check for damaged piston in 0 and bent valves. it will be pretty obvious what is wrong.
when head is on bench i put a bit of kero in the port, kero is 4x runnier than water so if is leaks past the valve, it will need lapping

will be cheaper to get another sonata engine, check compression before you buy it. good luck.
is the ecu mitsubishi style and plugs in to loom?
 
ive never removed a head before so i dont really know what im doing. might be best to leave it to the pros or something.
what causes a bent and/or open valve/s? esp just on 1 cylinder.
does that mean i have to just change the valves, maybe do a headgasket and put it back together?

you have to use mitsu bits as the plugs on the G4CP motor are different, unless you want to splice things back on. CAS and a few other things are different plugs.
Also the ECU casing is different, but it still can be fitted in with a bit of force. the plugs are the same in the CB's. looks to be the same for the CC's too
 
i dunno why only affected 1 cylinder. maybe valve stuck open and piston knocked it, maybe cam timing off, overrev, blocked injector has stuffed piston or burnt valve. dunno till you pull head off.
easy to pull head, bit more involved in putting it back on tho, but if you have done belt change already then thats the hard part.
my head has big allen bolts for head bolts (approx 10mm) you will need a allen socket to get these out as they are tight. start from the inside bolts and work evenly outwards. look on vfaq for how to remove head
try here, this is for a 1g so pretty close.
http://www.plymouthlaser.com/hreb2.htm
 
Ricki,

Sounds like the problem is more than just 'change the head gasket'...

Because it was running on 2teeth misaligned, this could have caused internal damage; ie valve hitting piston.
Zero compression obviously means pressure can't get built up in the cylinder as it's leaking from somewhere - could be the head gasket but are you losing oil &/or coolant? If not, probably not the gasket.. Could be the piston rings.

If the rings are gone, its almost not worth reco'ing the engine, and maybe buy another 2L NA? Really depends how much spare time you have to work on the car and how badly the cylinder bore was affected.
 
yea them sonata engines are cheap as. just grab another one and pull yours apart later.
mine was $100, i had to pull it out and it was non running, it had some electrical issues, but i dunno what they were.
look in gumtree

there are heaps of cheap sonata in gumtree perth, but only 1 under $1k in melbourne. you guys must advertise somewhere else
 
alex, no oil or coolant leak from what i can see..but when i started it up the other night it did puff alot of white smoke around the motor.
well im looking at new motors atm now. Ill take the rocker cover off and hopefully see if a valve is open or something.

jack, yea there is nothing really cheap atm. there is whole cars for around 1k but then I just think, if i add a bit more, I can just get a turbo motor and work from there. fk bent valves and ****** cylinders.


i have a 4g93t motor here. it seems like its too much trouble to fit that in the CB from what im reading.
 
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