Chasing P2188 code 2004 S60 2.5 T

JohnnyBee323 · Post by **JohnnyBee323** » 13 Mar 2018, 13:55

Getting P2188 code. Getting rough idle on startup when car that is already warm. Car seems to idle rougher when parked facing slightly downhill.

1.Replaced 02 sensors, Fuel Pressure Sensors, Boost Pressure Sensors.
-Still p2188 code
2. Smoke test, found vacuum leak in air intake pipe from MAF sensor to turbo. Replaced pipe and cleaned MAF sensor. Also very tiny leaks from some small vacuum lines.
- Car runs much better, but still getting the code p2188 and still rough idle on warm startup and also being downhill.

Could this be related to the fuel injectors too? I would think it if it were the small vacuum leaks causing this it would consistently run rough, not just on a warm startup or facing downhill. Any suggestions before I start dumping more money into this car?

Thanks.

Post by **chrism** » 13 Mar 2018, 16:18

p2188 = Too rich at idle.

Possibly you have dirty/leaky injector(s) allowing the residual fuel pressure to feed into the cylinder(s) when the engine is shut down. Then when you start it up it runs super rich until it burns off the excess fuel. Just a theory.

Does it smoke when it's idling rough?

When you shut it off, try immediately bleeding off the residual pressure through the schrader valve into a rag. Then see if it still runs rough the next time you start it cold.

It might not hurt to run some injector cleaner through it.

Post by **RickHaleParker** » 13 Mar 2018, 16:49

ECM-262A (P2188) Long-term fuel trim.

Diagnostic trouble code (DTC) information

Condition
The control module receives information from the heated oxygen sensor (HO2S) about the fuel / air mixture when idling at both the lower and upper part-load range. If the fuel / air mixture deviates from λ=1, the short-term fuel trim will compensate for this by adjusting the injection time so that λ=1 is achieved. When the short-term fuel trim makes an adjustment, the integrator median must be adjusted by the long-term trim. Diagnostic trouble code (DTC) ECM-262A will be stored when the long-term trim must be adjusted almost to maximum in the idle range.

Substitute value
none

Possible source

Upper limit:
intake air leakage
exhaust system air leakage
defective heated oxygen sensor (HO2S)

Lower limit:

intake air leakage
high fuel pressure
leaking injectors
defective mass air flow (MAF) sensor
contaminated engine oil
oil level too high
defective heated oxygen sensor (HO2S)

Fault symptoms
none

Post by **mrbrian200** » 13 Mar 2018, 19:41

The business of seeming worse when parked downhill would be engine loading against the motor mounts. When on an incline in 'P' the weight of the car torque loads the drive train against the engine mounts as if you were accelerating. This may or may not mean the mounts are worn as the engine RPM would normally be higher while accelerating. Your immediate issue is highly probable to be a leaky injector.

Post by **abscate** » 13 Mar 2018, 20:07

Look at the long term fuel,trim to see if it's at min or max for guidance

JohnnyBee323 · Post by **JohnnyBee323** » 16 Mar 2018, 11:28

chrism wrote: ↑13 Mar 2018, 16:18 p2188 = Too rich at idle.

Possibly you have dirty/leaky injector(s) allowing the residual fuel pressure to feed into the cylinder(s) when the engine is shut down. Then when you start it up it runs super rich until it burns off the excess fuel. Just a theory.

Does it smoke when it's idling rough?

When you shut it off, try immediately bleeding off the residual pressure through the schrader valve into a rag. Then see if it still runs rough the next time you start it cold.

It might not hurt to run some injector cleaner through it.

I think you are right, I have been thinking the same thing. It usually starts up cold with no problem. Only when it is warm, it starts rough and rumbles a little bit, and then levels off. Like if i were to run in and out of the the store for example, and go to start it up after it being off for a minute or so.

In order to keep cost down, what injectors do you recommend, and how do I diagnose which injector(s) are bad?

Thanks.

Post by **abscate** » 17 Mar 2018, 04:16

I think it's 25 bucks an injector to send them to MARRAN for cleaning and a full test report

JohnnyBee323 · Post by **JohnnyBee323** » 20 Mar 2018, 09:15

Here is a video link to my car starting up rough this morning. Please take a look and tell me what you think.

Post by **chrism** » 20 Mar 2018, 09:30

Did you try relieving the fuel pressure via the schrader valve on the injector rail when you shut the engine off? Do it as quickly as you can after shutting the engine off. You can spray it into a rag. Then wait a few minutes, like you said running into a store, and then start it up and see if it's any smoother.

Another thing you can do is to pull all the injectors out, but leaving them connected to the rail and the fuel supply line connected also. Then turn the ignition on to activate the pump and pressurize the system. Look to see if any of the injectors are dripping.

JohnnyBee323 · Post by **JohnnyBee323** » 20 Mar 2018, 10:05

No I haven't gotten that far yet. But wouldn't I be pulling other codes besides p2188 if there was really a problem with the injectors or fuel pressure? Wouldn't I be getting misfire codes too? I have a couple more small vacuum leaks my shop is fixing today, so hopefully that will do the trick.