QuestionQUESTION: Here is my question. My 99 300m occasionaly has a tough time starting and has a rough idle for awhile which occurs randomly, and also lately when i turn the key all the power is on but nothing will happen. If i try it like 3-4 times the car will eventually catch and start up. So i know its not the battery , im not sure if its the fuel pump starter, fuses. I am not getting a check engine light so got no idea. Please help!
ANSWER: Hi Tony,
There still code be codes stored in the memory of the engine controller, even without a check engine light. So try the ignition key:"On-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the odometer window to see the mileage change to show any 4-digit numbers preceded by a P. Let me know what they are and we'll go from there.
When you don't get any starter motor action, try moving the gear shift lever a bit off-center of the P or N position as the safety interlock may be slightly out of adjustment. Also, with a helper check in the box under the hood to see if the starter relay clicks or not when you can't get starter. If it clicks but no starter then starter motor or solenoid switch is suspect, if it doesn't click then the safety interlock/ignition switch/starter relay would be suspect. Let me know the result of that observation and we can go further.
The hard start/rough idle thereafter may also be due to an egr valve (exhaust gas recirculation) that is sticking slightly ajar which leans out the mixture too much to get a start or good idle. So that might be good to check out.
When you do a follow-up question tell me which engine size you have.
Roland
PS: Please 'rate' my answer, and where you see the question about 'volunteer of the month' please consider a 'yes' if you believe this response merits it. Thank you.
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QUESTION: First off Thanks Roland for your vast knowledge! Secondly I tried that on off trick and didnt see any code pop up, also I had my brother pop the hood and there is a click every time I try to turn the engine over. So it sounds like I will need to replace the starter than? I got a quote on the starter was like 450 to replace it the mechanic said. I found some for 120 online was curious if it was duable by yourself without huge amount of knowledge on the subject.
Thanks again!
AnswerHi Tony,
Yes, assuming that the click came from the starter relay, although you might want to check that the relay's contact points are actually conducting current to the light green wire that goes to the starter motor. You could use a voltmeter or glow light at the light green wire at the starter motor solenoid or you can also find that wire on pin 6 of a 10-pin gray color disconnect located on the driver-side of the engine at the front/top area (probably hidden under the intake manifold, however). You might alternatively sneak an insulated wire into the socket for the relay that is attached to that wire (pin D) and then put the relay back in as a way of accessing the wire. The relay is the fourth from the in-board edge of the box. If you verify that the light green wire is being powered when the relay clicks, then you can conclude that the starter motor needs to be removed and rebuilt (which is my recommendation if there is a starter/generator shop near you).
The 3.2/3.5L starter install involves a few tricks, one of which requires a floor jack. Here is the procedure:
After disconnecting battery and raising the vehicle,
remove one nut on the catalytic support bracket.
remove two nuts from catalyst support bracket mounting.
remove two bolts and one nut attaching starter to engine
remove battery positive feed wire
remove starter solenoid assembly from trans housing
position starter to gain access to posi-lock wiring connector
position jack beneath engine and slightly lift to relieve pressure from left engine mount (use wood block spacer to protect pan)
remove three left engine mount mounting bolts from engine block
jack engine up slightly to give more room to maneuver the starter
slide rear of starter out between catalytic converter and engine mount
disconnect posi-lock starter solenoid connector
remove starter
Install is the reverse.
Roland
