REALLY rough idle

[ron1004]

Originally Posted by sportage4x4

betcha its got a few bent valves!

I must say I was also thinking along those lines (cambelt a tooth or two off, or valves damaged from a previous cambelt destruction), but was puzzled that it runs well except for the rough idle.

[Raven1210]

maybe bad gas, or fuel filter clogged. I had bad idle and it was a fuel filter clogged

[yyskuby]

Had a similar Idle problem - was even getting a P1166 code. Gapped the plugs down to 0.030 and fixed the idle and no more code. Don't understand why the P1166 went away - but as long as it works.

[mark458]

I have checked the timing and heres an interesting thing... The kia manual says the i on the intake and the e on the exhaust should be straight up which they are how ever a kia dealer said there are 2 white dots one on each gear that should be up but one is up one is down...I also noticed that if I put a sheet of paper over the maf and cut off almost all the air... it runs perfect at idle...

Also compression is good

also vacuum at idle is very low so low the brakes barley work.

Could this be because of the maf???

[Raven1210]

nope it means you have a vacuum leak somewhere in your system

[mark458]

Checked all the vacuum and found nothing wrong.

[ron1004]

Originally Posted by mark458

I have checked the timing and heres an interesting thing... The kia manual says the i on the intake and the e on the exhaust should be straight up which they are how ever a kia dealer said there are 2 white dots one on each gear that should be up but one is up one is down...I also noticed that if I put a sheet of paper over the maf and cut off almost all the air... it runs perfect at idle...

Also compression is good

also vacuum at idle is very low so low the brakes barley work.

Could this be because of the maf???

That sure confirms a fairly bad vacuum leak.

You could try using a can of starter fluid and spray that in strategic locations and when the idle picks up then the leak is in that area.

The brakes are bad because the lack of vacuum for the brake booster.

Also check the Non-Return valve in the vacuum line to the brake booster, and the one used for the Positive Crankcase Ventilation (PCV valve).

[mark458]

...non-return vavle? I dont see any valve in that line. Also I have sprayed every square inch of the intake/vacuum system and found nothing.

And yet all the error codes Im getting point to vavuum! Im about to throw this thing in the lake and file it stolen. This is the LAST kia I will ever buy unless someone can tell me exactly what to fix.

[ron1004]

Originally Posted by mark458

...non-return vavle? I dont see any valve in that line. Also I have sprayed every square inch of the intake/vacuum system and found nothing.

And yet all the error codes Im getting point to vavuum! Im about to throw this thing in the lake and file it stolen. This is the LAST kia I will ever buy unless someone can tell me exactly what to fix.

Often the non-return valve is on the end of the vacuum pipe and it plugs into the brake booster, much the same as the PCV in the camshaft cover.

From the KiaTech site in my sig:

CHECK VALVE

The check valve is pressed into the vacuum hose. The arrow on the hose indicates the direction of hose installation (toward engine).

1.Remove the clamps and remove the hose (with the internal check valve).
2.Apply a suction and pressure to the hose from the engine side. Verify that air flows only toward the engine. If the airpasses in both directions or not at all, replace the vacuum hose (along with the check valve).

http://www.kiatechinfo.com/data/manu...G/bj2c018a.gif

[mark458]

I looked at that hose and the valve is fine.

Compression
1. 200
2. 210
3. 210
4. 210

Another weird thing... I removed the plug wires and put them on backwards. 1 was on 4 ect... The car still cranked up and ran the same!