QuestionQUESTION: Our '01 Sebring Convertible just started idling very rough
one day. I recently had to replace the camshaft sensor
(check engine light came on) and I thought that might take
care of the idle problem as well, but no change in the
idle. There were no other codes. Plugs are new, I've run
Lucas fuel system cleaner through it. Not sure where to go
from here.
ANSWER: Hi Jeff,
You didn't say which engine is in the car, so I have to assume a 2.5L V-6. If that is not the case let me know. Also assuming there are no codes, then I would believe that there is something wrong with the mixture, the most likely is the egr valve. The EGR valve may be stuck, most likely ajar. So you need to try and get it freed up and moving again so that it will be closed when the engine is shut down, otherwise it will be difficult to start and to idle.
The first thing I would do is check the mechanical function of the egr valve which is located along a pipe that runs from the left exhaust manifold (on the side of the engine facing the front of the car) to the intake manifold area (where the incoming air in the large rubber tube enters the throttle). That valve is metal and has a round fitting with a vacuum hose attached, mounted on the top of the valve, and the round part is attached to the main body of the valve by a sort of saddle. Inside the open saddle you will see a metal rod (with a slot) that connects the round top fitting to to the valve body. That rod is a stem on the valve and it is supposed to go in and out in response to the engine vacuum which varies with RPM and throttle opening (gas pedal position). Take a spray can of WD-40 or other penetrating lubricant and spray the stem where it enters the valve body and then use a regular screwdriver blade tip inserted in the slot to lever the valve in and out to try and free up its motion. Also check all the rubber vacuum hoses associated with the valve and a nearby vacuum solenoid valve. If the valve seems to open (against the action of a spring) and close firmly by the spring action when using the screwdriver blade to facilitate the motion, then you should be able to now start the engine. You can, once it is idling, check that the valve stem moves when you rev the engine from idle to 2500 rpm and back to idle. If it still won't start, then removing and cleaning the interior of the valve, or buying a new one if it seems too crudy and corroded inside, is the next step.
Roland
---------- FOLLOW-UP ----------
QUESTION: It is the 2.7L engine. Looking for the valve right now. No
problem starting or with it dying, just idling very rough.
ANSWER: Hi Jeff,
The EGR is mounted on the rear of the engine, below the throttle body. It gets exhaust gas from the right side exhaust manifold and feeds it into a bifurcated tube into each of the intake manifolds. Because it is not vacuum operated but rather electrically it is not serviced as I described for the 2.5 V-6, but it would still be worth removing the valve and looking at the intake and output side of the valve for possibly being clogged so that it is stuck partially ajar. Here are the steps for its removal:
Disconnect negative battery cable
Remove air inlet tube and resonator
Remove throttle cable bracket and reposition
Remove egr tube mounting screws at intake manifold plenums
Disconnect electrical connector from solenoid
The egr valve attaches to the rear of the right cylinder head
Remove egr upper tube screws at egr valve
Remove egr valve mounting screws
Remove egr screws from egr lower tube at exhaust manifold
Remove egr and lower tube as an assembly
Clean gasket surfaces. Discard old gasket. If necessary clean egr passages.
To reinstall:
Loosely install EGR valve and lower tube, use a new gasket between tube and EGR valve
Install EGR valve to rear of chlinder head, do not tighten screws
Loosely install screws to lower EGR tube to exhaust manifold
Install rubber silicone seals on intake manifold end of
EGR tube
Install upper tube into the intake manifold being careful to be sure silicone rubber seals is correctly installed and undamaged.
Install new gasket between the EGR valve and tube and install bolts
Tighten EGR upper tube to intake manifold plenum screws to 80 inch pounds
Tighten the EGR tube's to EGR valve bolts to 95 inch pounds
Tighten EGR lower tube to exhaust manifold screws to 200 inch-pounds
Attach electrical connector
Install the throttle cable bracket to intake manifold
Isnall air inlet tube and resonator
Connect battery
---------- FOLLOW-UP ----------
QUESTION: If it is bad should there be a code?
AnswerYou will recall that we exchanged q and a's earlier this month about your car. I am competing to be recognized as 'expert of the month' for November, and the voting ends Sunday afternoon. If you would consider giving me a vote, that would be most appreciated. Use the "Thank/rate" tab below where you will see "nomination?" and then change the 'no' to a 'yes' to give me that support. I hope things are well
Hi Jeff,
The tests for the egr function are more gross, in by belief, than would be able to detect a slight leak when it is supposed to be closed (and thus leans the mixture and causes rough idling). There are codes for it not working at all, being way out of position, etc. so absent anyother codes it is a possibility that should be considered. Other than looking for vacuum leaks and inquiring whether, when you installed the cam sensor, that you pressed the tip against the metal surface that it senses and held it there while you tightened the retaining screw?, I have no other suggestions as to how you have the rough idle with no codes.
You might want to look for vacuum leaks using a spray can of starter fluid, in very brief bursts (don't want to start a fire) in the vicinty of the intake manifold edge while the engine is idling to see if you can detect a leak via a change in the idle situation. Also look for any disconnected or cracked vacuum lines.
And you might want to buy a new spacer to put on the tip of the cam sensor and try reinstalling it. And you could keep waiting for a relevant fault code.
And if none of those materialize, then check out the passageways of your egr as the last resort.
Please let me know what the solution was when you find it.
Roland
