Difficulty Starting Engine and Uneven Idling

[Siewss]

the iacv is easier to check than your hoses leh. check the iacv first.

 

Thanks for advice. That should help.

 

[Siewss]

Most likely your idling valve or IACV is clogged.

Pouring STP engine cleaner to the oil sump will not help.

Need to remove the IACV to clean.

IACV is in the air passage, not the fuel or oil lines.

 

Just curious, are you using stock air filter or some "high-performance" air filter ?

 

I'm on stock filter, though I bought a Hurricane filter which I used for all of 1 week.

[Siewss]

if you can still find carburettor cleaner, take out your air filter, spray some after the AFM, then reassemble everything, then start the car up, go for a drive, see if anything changes.

 

Not quite sure how to do this because I'm not comfortable spraying fluids into the air hose, and neither do I know how much to spray. I'll just leave it to the professional.

 

[Minikong]

I encountered a new problem upon reaching Port Dickson 2 days back:

 

1) Difficult to start - the engine normally just fires up at the turn of the ignition, but after parking for 1 hour at the resort carpark, the engine refused despite a few series of cranking. At the end, I got the car started after applying gas through the pedal. It's still the same today.

 

2) Idling is uneven - when in the past the engine will turn at 850rpm thereabouts (with or without aircon), now the rpm fluctuates between 700~1000, depending on the aircon. Vibration can also be pronouncely felt the cabin, when in the past such intrusions were completely absent.

 

Everything goes back to normal once on the run - no power loss, smooth pickup and cruising....till the next stop.

 

Thinking back, I can only relate this symptom to one thing I did wrongly. 2 weeks ago, the engine was idling quietly when I absent-mindedly cranked the engine. There was that all familiar sandy-rasping sound, but nothing happened at that point.

 

Anyone can advice what could have gone wrong?

 

it might be your fuel pump, as i also encounter the same problem with you, done a compression test, and they said it the fuel pump

[Siewss]

it might be your fuel pump, as i also encounter the same problem with you, done a compression test, and they said it the fuel pump

 

Sounds ominous. I'll look through the warranty agreement again - hope fuel pump is covered if this is the real cause of my problem.

[Yeobh]

Compression test cannot determine fuel pump pressure problem. For fuel pump and injector your mech need a fuel injector pressure tester .

 

Ist photo - compression tester

2nd photo EFI pressure tester

Edited October 25, 2010 by Yeobh

[MLS]

Bro, I am facing the same issue as you too. Mine is a CS3.

 

The rpm is normal when aircon is off.

When aircon is on, the rpm drops to 600 and there's vibration felt.

 

The issue is due to the idling valve/idling motor like some bros mentioned.

I've yet to have it changed cause I have the workshop tuned the rpm to be higher for me for the time being. No stock for item.

 

 

[Kb27]

I'm on stock filter, though I bought a Hurricane filter which I used for all of 1 week.

[Kb27]

Compression test cannot check fuel pump.

 

It is to check piston rings sealing in the combustion chamber.

 

Fuel pump/fuel regulator must be checked by another device.

[Yeobh]

If the blow -by is so heavy, chances the compression and scrapper rings are gone.

[Roadhogger]

hi guys...i got almost the same issue...i got difficulty starting only in the morning. My idling can sometimes drop till 500 to 600 rpm. I am suspecting the fuel filter. Any inputs?

[Siewss]

Bro, I am facing the same issue as you too. Mine is a CS3.

 

The rpm is normal when aircon is off.

When aircon is on, the rpm drops to 600 and there's vibration felt.

 

The issue is due to the idling valve/idling motor like some bros mentioned.

I've yet to have it changed cause I have the workshop tuned the rpm to be higher for me for the time being. No stock for item.

 

My problem with the irregular idling is independent of the aircon. Today another symptom developed - whereas in the pass few days, the irregular exhaust throb is accompanied by slight vibration, now it feels like the engine is missing a beat every 5 secs, with a shudder that can be felt throughout the cabin. Seems like the problem's getting worse.

 

Hope you can get it fixed soon.

 

[Siewss]

The other problem is the blowby gas.

 

It is fed back into the throttle body.

If your engine produce a lot of blowby, then these oil gases may clogged up the valve.

 

To minimize this blowby, install a oil catch tank.

Also some engine oil has high moly content which may reduce blowby.

 

I drive a diesel van. With hurricane or K&N filter, it will be suicide. Now even without them, my MAF sensor didn't worked well, until I cleaned it quite thoroughly. That bloody MAF will cost me almost $300, don't play with it.

 

I suppose the valve is meant to be cleaned once every few years. I'm not sure if my engine produces a lot of blowby, but I thinking installing an oil catch tank will likely void the warranty.

 

I'm not about to play with my filter anymore - stock is still best.

 

[Minikong]

Sounds ominous. I'll look through the warranty agreement again - hope fuel pump is covered if this is the real cause of my problem.

 

 

got warrently 1, mine also replaced a high pressure fuel pump for free when under warrently

[Siewss]

Ok, here's the chronology of events:

 

1) Sent the car to the workshop, explained all the symptoms to the service consultant, and told him the icv and fuel pumps are likely suspect

2) Service consultant called at noon, told me they found no trouble, and explained what they have done (diagnostics reading, compression test, check idle valve condition, battery)

3) Told service consultant to recheck again, particularly hot starting, with air con on and listen to exhaust note

4) Service consultant called in the evening, told me they retested everything based on 2), but decided to go with ECU reset

5) Went down to workshop for collection. Again was told by service consultant they found nothing wrong. But the ECU reset should help, and I should monitor over a few days

6) Give the car a once over, and checked the car out - the engine fired up immediately, no problem with that. But that's when the tachometer went haywire - the RPM dropped from the already low 700rpm to a steady 500rpm, with or without the aircon on. The whole engine was rocking on on its mounting. Service consultant acknowledged the problem.

7) Decided to drive the car home, but told the service consultant perhaps the ECU is trying to recognised the driving pattern and may take a while to stabilised, and if symptom remains, will drop by the next day to test the car more thoroughly

8) Drove the car home - no problem at all. Parked the car

9) Tested the car again after 3 hours of cooling down. The same exact symptom prior to the workshop check surfaced - difficulty in starting, rough idling

 

 

[Crazecow]

Then I suggest you go to another WS for help.

[Siewss]

Then I suggest you go to another WS for help.

 

I went back to my AD, since my car's still under warranty.

 

Anyway, I sent it in again today - was told to leave it at the WS overnight.

 

[Siewss]

After 2 days at the workshop and changing the high pressure fuel pump which cost almost a $1000 (covered by warranty), the problem stubbornly remains.

 

The good thing is, the engine doesn't drop to the drastic 500rpm. The bad thing is, it does go to 700rpm, where it'll idle bumpily and unevenly, with the occasional "hiccup", not to mention the uneven exhuast note. Starting the car still requires long cranking and the occasional "gassing"

 

When turning off the engine, there's that rattling sound akin to shaking rubber pellets in a tin can, followed by semi-violent juddering of the engine before shutting down.

 

Travelling at low speed, there's the rasping feeling on the pedal, or the engine, I'm not sure, which felt like running over sand rather than smooth tarmac.

 

I searched for some aussie site and found some some owners who reported similar problem, and they self-diagnose as EGR valve. They got it cleaned and the engine goes back to the same smoothness he used to enjoy. I'm concern that if my case happens to be faulty EGR valve, I may be facing other related problems like O2 sensor failure, high FC etc...