Thank you in advance for considering my question about engine stalling and my very, very short post. Herein, I present here the following:
A) A short description of my 1993 400E's symptoms as I understand them;
B) My check list ;
C) My 4 questions and
D) A profuse well intended thank you.
By way of introduction, I am a new Forum member; hardly a skilled mechanic; and I hope I am posting my story correctly. If not, please correct, and I won't take it personally.
A. Problem Symptoms and recent performance maintenance background:
With my 400e (1993, last Vin digits 930922, 152k) about 2x per hour when I am driving (at almost speed) my engine cuts off, the dashboard lights up ABS, Check Engine, SRS etc. This has been going on for about 1 year. This drives my girlfriend crazy who is anxious for me to fix ASAP.
When this happens, I shift in neutral, restart and I’m on my way, that is until the next time. And I assure my gal that I will attend to this soon. Clearly, I have been remiss.
Also, perhaps on a related matter, in the past week, the engine has been running a bit rough when I start.
Side note, but perhaps of interest, in terms of fuel purchased, I almost always (95%) purchase Premium at my neighbourhood Costo in Los Angeles. And I'm pretty good about following scheduled maintenance.
B). Checklist to find 'The Cause':
After combing the archives this is what my checklist looks like (freely plagiarizing without directly attributing the various members inputs to save writing space (apologies in advance). I will thus….
1. Check Crankshaft Position Sensor; TDC Sender; Front of Engine (I noticed that there were two listed for sale at
Your Parts Search Returned 2 Part(s)
My hope is this one: TDC sensor Crankshaft Position Sensor; TDC Sender; Front of Engine ($41.69) -- as I understand, the crankshaft position sensor governs ignition timing so if its malfunctioning then EZL ignition module won't function properly.
The reason why I’m hoping that it’s the last part number is because it’s about 1/3 rd the cost of the other.
Also, I know it’s such a newbee question, but is the engine serial number the same as the VIN?
I ask this because the part number says the less expensive one is For models with engine serial number through 010028.
Of course, I’ll call the dealer, provide my vin and see what the part number is (same for any parts I refer to in this short (ha ha!) note;
2. Clean MAF;
3. Check Vacuum Leaks;
4. . Check Alternator noting that I plan to drive with my headlights on, fan blowing on high, stereo cranked up during the day and see if it will shut off again., and will step on my brakes at high speed. Assuming the battery is good, I have read that if it turns off that could mean my alternator is not putting out enough juice to recharge the battery;
5. Throttle slide issues. I plan to clean the throttle body and as well remove the MAS sensor and clean the throttle body interior(butter fly flap) and surrounding areas with carburetor cleaner using a tooth brush and plastic scowering pad. If I go this route, it has been recommended that I purchase a new boot for MAS sendor before starting;
6. I do plan on getting spark plugs, and will inspect my dist cap and rotors. If they look a little crispy then I’ll pop for some new ones as well as checking the inside of the ignition wires that go into the cap and looking for corrosion on the terminals. Any recommendations for spark plugs and wires (not just types, but part numbers?);
7. Check fuel pump relay while noting that Fuel Pump Relay should not cause ABS light to go on; (and check fuel pressure regulator)
8 .OVP=Over Volt(age) Protection. Common stalling problem (but I’m not sure at this point if 400E has OVP; rather I have read that in the 400 model the OVP has been incorporated into the base module that sits in the back left corner of the engine compartment next to the firewall looking like a proud battery);
9 Check the ground on ICU (connected to the L/H inner fender);
10. Check for bad stoplight switch; noting that stop lamp switch is under the driver dash, operated by the brake pedal lever;
11. Check for injector disconnect
12. Check for failed throttle body idle/WOT switch and a failed throttle linkage idle switch;
13. Pray it's not yet the harness and / or the the TBA (throttle body actuator);
C. My 4 questions
1. Well, so am I missing anything? If so, what?
2. And is my diagonstic-ish order a reasonable one to in which to proceed in?
3. If I do want to read the computer codes, does anyone have any suggestions on which posts to read?
4. Also, as I've perused through an electronic copy of the Mercedes Benz Manual, I notice it refers to genuine Mercedes Parts list. Any ideas on where do I get that? Or what it's called? (Anyone? Ferris?)
D. Final Thoughts
Thank you so much for considering my case, and I hope of course, as I learn more to post my own experiences (failed or successful),