darksydedaddy

I have a 2002 OZ. My wife got caught in a heavy downpour, and the Cold Air intake took in cold water instead. The result of the water ingestion was catastrophic connecting rod failure on cylinder 1, punching holes on both sides of the block you can literally see through. I have replaced the long block, but I am still having a run issue. The symptoms include: rough idle, lower than normal power, slow throttle response, and extremely heavy fuel use, with heavy fuel smell at the exhaust.

Compression : 170+\- 3% across all four
Cam Belt is spot on marks
plugs are good
fuel pressure is difficult to test with no test port, but when I disconnect return line with engine running, fuel comes past regulator, so I assume that pressure is ok

I replaced the upstream o2 sensor
I replaced the IAC
I replaced the MAF (however, it was from a 16 valve engine on a Galant of the same year. Has a different number on top, but all other appearances are identical)

Scantool.net software reads lean condition, the fuel trims are whacked out
Everything points to intake air leak, but I can't find one, I have listened, felt, and sprayed various test liquids all over the thing. I have gone over it again and again, and I am running out of ideas. Help.

Edit: 7/17/2014: I have tried to add the Data files from the OBDII wiz scan tool and Laptop that I am using, but I don't know how to make them play on screen, and the attachment manager does not recognize .tldz format to attach.

I still have stumble at idle, very soft power at part and WOT openings, and get about 5 mpg running very rich. CEL says lean condition. 3 MAF meters used, 2 MAP sensors used, good temp sender, cam timing is spot on, compression is good, no plugged exhaust, O2 sensors bench tested as good, no unmetered intake leaks that I can find, TPS tests as good, clean injectors, new plugs and wires, replaced coil packs, car ran perfectly before, so no reason for fuel pump to be faulty.......AAAAAAAAGGGGHHHHH FARGING CORKSOCKER CAR!! I am stymied. Any ECM tests I can run? But I can't imagine why that would have failed, either.

RT78

I'd give the TPS a test, I'm thinking maybe it got a bit wet from the water and went wacky. Maybe the injectors..... Hang on, I ran part #'s for the MAF. It's a different MAF for the Galant(MD336501)than the Lancer(MD343605), that could be the issue. If that's not it I'd look at the MAP, you have all the symptoms of a failing MAP.

darksydedaddy

I checked the TPS after your post, it reads correctly with a voltmeter. The MAP is attached somewhere just downstream of the throttle butterfly, yes? Is there a test procedure that you know of?

The MAFs do have a different numer on the top (501 vs 605), but the resultant run condition was the same, so I think my original wasn't bad, and I think they function the same, but no one is able to confirm.

I like the MAP idea, I will look into that.

RT78

Ok so I think we can rule out the MAF since there was no change in condition with replacement. As far as the MAP, that's the spot. Unfortunately I can't find a testing procedure on either alldata or mitchelldiy. All I can find is by probing the sensor signal wire and checking voltage value when you apply vacuum and looking for the voltage to smoothly decrease. Apparently you can just actually suck on the sensor to apply vacuum if you don't have a vacuum pump(doesn't sound too pleasant to me).

darksydedaddy

Tested MAP as follows:

Removed from manifold, back probed green wire to get 4.78 volts.

I bought a Mity Vac.

vac @ 5 psi - 3.9volts
vac @ 10 psi - 3.0 volts
vac @ 15 psi - 2.4 volts

Now I am back to vacuum leak, or MAF sensor didn't make a difference because it is the wrong one.

Wish I had a smoke tester.

RT78

What kind of O2 sensor did you use? The reason I'm asking is another member replaced his with what was supposed to be a Denso from rockauto, it wasn't and he had fuel trim issues and the sensor voltage wasn't switching how it's supposed to. What is the short term trim in relation to the long term trim?

jwick76

iTrader: (1)

similar issue with mine, from a carwash and my dumbace not putting the splash shield over my filter, with the stupid open evo seibon cf hood i have. Replaced MAF, and then had to replace IACV...it runs now, but the idle is weird. When I put SAS mode in evoscan the idle actually shoots up to 2500 even with the BISS closed. When I put it back to normal, it idles correctly after the 2500 startup...maybe 5-10 seconds before normal idle.

I now have a water repellent pre-filter installed over the filter. And if your CAI goes below the headlight line, I would suggest installing a bypass filter.

and that MAF is different, you need to get the exact same year and model. That is a larger MAF and will throw off all your ECU values. The numbers make a HUGE difference. For instance, I use a 501 MAF from a 94 Galant on mine...had to adjust the MAF tables to make it work. I can't use a stock MAF on my 03 OZ anymore without flashing the ROM.

99% sure that's your problem. The MAF run red hot, and a bit of water will short the circuitry right out.

darksydedaddy

I appreciate the input.

I will try to find a local (proper) MAF, I was trying not to throw expensive parts at it if I wasn't sure. I appreciate results from a similsr aituation. I wonder why the MAF is different, the engine had a very similar intake tract, and the exhaust and block looked identical. Updates to follow.

jwick76

iTrader: (1)

For a better understanding of the MAFs you can use, and what goes into getting them to work, go here: https://www.evolutionm.net/forums/la...tep-guide.html

The Galant for that year had a larger 4cyl engine and also came in a 6cyl model, both using a larger MAF sensor:
140-hp, 2.4-liter I-4 (regular gas)
195-hp, 3.0-liter V-6 (premium)

You can get away with different years, but if you're not sure what you're looking for then hit up a junkyard. Supposedly MAFs from the following years are interchangeable, but I'm not 100% on these numbers:

LANCER 02
LANCER 03 exc. Evolution
LANCER 04-06 exc. Evolution; 2.0L (4 cyl)
LANCER 07 (ES, 2.0L)
MIRAGE 98-02 (1.8L)
MONTERO SPORT 97-99 2.4L (4 cyl)

I can normally find them on eBay for around $50. http://www.ebay.com/itm/2002-2007-MITSUBISHI-LANCER-AIR-FLOW-METER-/190995141553?pt=Motors_Car_Truck_Parts_Accessories &fits=Year%3A2002|Make%3AMitsubishi|Model%3ALancer &hash=item2c783293b1&vxp=mtr

darksydedaddy

I used a Bosch direct replacement O2 sensor from Auto Zone.

darksydedaddy

I have purchased and installed a replacement MAF, and there was no change in power delivery at full throttle, still sluggish. Idle quality is better. Catalytic convertor clogged? Restricting exhaust flow? Can I recheck my cam timing by using TDC on the belt cover and the mark on the balancer, instead of removing all of the belts, and the balancer, and the cover to see the crank gear? Would you trust that?

I am now a bit lost, as if there was a gross intake leak, fluids should find it, or I should hear it.

How do you guys test fuel pressure without a test port on the rail?

RT78

Ok, before you start going crazy tearing things apart over there, let me know what the short term and long term fuel trims are, plus the voltage of the upstream and downstream O2's with the car running. Wait, I just read in your original post that you were getting a lean condition, if I'm right the voltage of the upstream O2 is going to be staying around .100-.200mV, if so it's the O2 sensor, it should be switching from low to high, for example .150, then .750 and back and forth.

jwick76

iTrader: (1)

Are you using Mitsulogger or Evoscan? Run some logs so we have some info to look at.

So to recap: new MAF, new IACV? You only replaced the bottom of the engine, or did you replace the head as well?

Did you replace the MAP sensor on the intake? If you got water all the way into your engine, I would assume all sensors other than the TPS were junk.

If it's idling well and you're noticing it getting sluggish when getting up to speed and sending a lean code, I would start with replacing the MAP (new ones on Ebay are like $70). If you still get the lean code and you replaced the upstream o2 sensor already, then I would pop your injectors and clean them by soaking them in brake cleaner for a bit (if you don't have an ultrasonic) and making sure they are sealed tight (those o-rings can be a bit dicey if you don't seat them right).

Make sure your FPR doesn't have any damage, and that the vaccuum line is good. I've had a shop nick this before and it caused lean fuel conditions and sluggish power under load.

And finally, check your coils. I've had these get fried from water damage coming in through the Seibon hood I have, and while they still functioned...they would start to miss at higher RPMs.

if your cat was fine before, it should be fine now...the lean code is being thrown by the first (upstream) 02 sensor, so it's prior to the cat anyway. Assume issues related to MAP, injector/injector seals, FPR vaccuum/function, and finally coils.

jwick76

iTrader: (1)

I'm assuming all of this was due to using the Manual Transmission style CAI? It terminates so low on the car that one good puddle and you're done for. I had this prior to my short ram intake (as it still fits with the AT transmission, just needs elbow grease to get it by the dipstick stem) and played it safe with a bypass filter:

it's like putting a whole in your straw so you can only suck water up so far....probably won't work at WOT, but if you see the puddle coming you can plan accordingly.

RT78

I mentioned in a previous post about the other member having a similar issue. He replaced the O2 sensor but the one he got was either faulty or for some reason it was sending an errant signal to the pcm. The result was a code for a lean condition and the voltage of the O2 sensor wasn't hitting high enough to be read by the pcm as a rich condition so it just kept adding fuel. Check the voltage of the upstream O2 with the motor running and if that's the case(I already mentioned what to look for voltage wise) replace it with a Denso(I'd never put Bosch in an import) that replaces part #MR578634. That's the factory part # for the upstream O2.