paul65k

Hi Guys,

Had the dreaded "Check Engine" light come on late Friday night for the first time. I bought an OBD II reader today (Costco $20) and checked the codes and here's what I got;

1. P0400 - Exhaust Gas Recirc - Flow Malfunction

2. P0105 - Manifold Absolute Pressure (BAR), Pressure Sensor Circuit


Is #1 an ERG valve replacement? No clue what #2 would be or if this is just a by-product of the first. I haven't driven the car since resetting the error codes and while I did restart the engine the "Check Engine" light did not come back on. Is it likely that this could have been a spurious error code or could this be shades of something bigger to come??

My car is an 02 model without Kompressor and has ~74K miles. I am covered under a Chrysler Maximum Care Warranty so if this is something that would e covered I'll certainly have the work done at the dealer but if this is considered a maintenance item I'll likely have my local indy take care of it.

I would definitely appreciate any insight some of the more technical guys here might have if you wouldn't mind.

Regards,
Paul

RichardM98

First, clearing the codes and waiting to see if they come back is always a good idea. Also, as you mentioned, it is often true that one code will trip another so if you fix the issue with the first they both disappear.

The EGR is also part of the crankcase ventilation system which usually involve some hoses running to the valve covers. These hoses can become plugged especially in cars which don't get driven long enough to reach full operating temps. I'd suggest having your indy take a look.

Good luck.

paul65k

Well.............here's how my day went.

I was on business trip and came down with a cold so I figured out how to rearrange my schedule to come home early. Had to transfer flights so of course last minute had me in a middle seat with the 2 biggest people on the plane on either side (Of course)

We finally got to my home airport and I was happy to get off the plane and was so looking forward to the 20 minute drive home and some chicken soup and turning in early....and what do I find??? walking up to the car it looked like the left rear tire was a little low and not only was it low but it was as flat as a pancake so I called AAA and 45 minutes later I was on my way with a screw in the sidewall of my brand new Hankook tire

Well when I finally got on the road and the end was in sight.....that damn light came on again.......needless to say I didn't pull the codes yet but I'm guessing it will be the same stuff. I'll pull the engine cover tomorrow and see if there is anything amiss with the hoses and then when I don;t see anything I'll take it to the Indy.........thanks for your advice!

Cheers!

RobertG

I'm guessing that the egr is sticking open from carbon build up and causing drop in the manifold pressure and triggering the other code.

paul65k

Thanks....is that likely an EGR replacement or simply something that typically needs cleaning?

RobertG

No, no special cleaning needed.
Do you drive this car often?
Try TECHRON (sp?)fuel system cleaner and some spirited driving.

paul65k

This car has become my daily driver but still under 1000 miles a month.

Costco just came out with a $5 off cupon for a Techron 6 pack and I was going to buy some and run it through all the cars.....I'll double up on this one...thanks

PS....the spirited driving is definately a benefit that I look forward to

paul65k

Just got back from Costco.....you can get 6 bottles of Techron for $11 after the coupon....less than 1/2 the price of buying a can at the Chevron station or auto parts store.

I put 2 in and will drive it this weekend and see if I can get it cleaned out.

Thanks for all the help!

charliev68

saw this old thread.

i have a clk430 throwing these exact codes.

is the MAP/Baro sensor at the bracket on the water pump?
would faulty sensor or hose also throw the P0400(egr) code?

RobertG

Yes the sensor or it's hose will set a code but not an intermitent code like OP's .

charliev68

okay...solved the problem using alldata.
in a nutshell, if your car is throwing P0105 with P0400 and is running fine, it's a bad vac. line.

a malfunctioning MAP/Baro sensor will not activate the EGR hence the 2 DTC's.

btw-the MAP is in front of the engine, right next to the idler pulley on a bracket with another sensor.

hope this will help someone in the future.