Intermittent No Start
10-16-2018, 12:39 PM
#1
Junior Member
Thread Starter
Intermittent No Start
I am have an issue starting my vehicle when the engine is cold - sometimes in the summer months but more frequently in the colder winter months. The vehicle is a 2003 W211 E55 that has been well maintained with the normal issues these cars encounter eventually - airmatic, sbc, etc. The vehicle cranks without any start in the manner associated with a faulty cps. Initially I suspected this was the culprit especially given the fact that my rear main seal has started to leak badly and I believe the sensor is getting coated with hot oil during extended driving periods. However, the part that is making the diagnosis challenging is that the issue is leading me to a fueling fault. I can get the vehicle to start by spraying starting fluid into the throttle body. It will stutter repeatedly but eventually will start. Another issue which may be related is a rough idle. Like the no-start, the idle issue is intermittent - sometimes it idles perfectly and other times it is extremely rough. I am hoping the E55 community has encountered this or can help analyze the issue to lead me to the faulty component(s). Maintenance background - I have a new cps and rear main seal which I plan to tackle shortly with new motor mounts. I have replaced valve cover gaskets, coil packs, plugs/plug wires, fuel dampener, injector o-rings, and O2 sensors within the last six months. Fuel pump/sending units were replaced a few years ago. Assistance/feedback is greatly appreciated.
10-16-2018, 01:01 PM
#2
MBWorld Fanatic!
Check the fuel pressure at the fuel rail when it doesn’t want to start and see if it’s getting fuel.
If no pressure then pull the fuel pump relay and check the socket for any burnt areas. (not sure where a 2003 is. Mine is a 05 and was in the trunk right side behind the carpet panel).
Oh and there was 2 relays next to each other in my car so if you have 2 next to each other make sure you replace the correct one.
I thought I had a pic of where it’s at but don’t sorry.
I had a periodic no start issue. I Replaced the CPS and that didn’t fix it.
Catching the problem was tough since it was intermittent and I was away from the shop when it would happen. It finally happened while at my shop and we did a fuel pressure test. No fuel was getting to the fuel rail. I replaced the relay and haven’t had an issue since.
If no pressure then pull the fuel pump relay and check the socket for any burnt areas. (not sure where a 2003 is. Mine is a 05 and was in the trunk right side behind the carpet panel).
Oh and there was 2 relays next to each other in my car so if you have 2 next to each other make sure you replace the correct one.
I thought I had a pic of where it’s at but don’t sorry.
I had a periodic no start issue. I Replaced the CPS and that didn’t fix it.
Catching the problem was tough since it was intermittent and I was away from the shop when it would happen. It finally happened while at my shop and we did a fuel pressure test. No fuel was getting to the fuel rail. I replaced the relay and haven’t had an issue since.
Last edited by tlambert; 10-16-2018 at 01:08 PM.
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Punisher10mm (10-16-2018)
10-16-2018, 01:08 PM
#3
Junior Member
Thread Starter
Tim,
Thanks - have been reading thru the bbirdwell relay thread. I will probably replace it as I never looked at it when I replaced the sending units.
Regards,
Scott
Thanks - have been reading thru the bbirdwell relay thread. I will probably replace it as I never looked at it when I replaced the sending units.
Regards,
Scott
10-16-2018, 02:39 PM
#5
Junior Member
Thread Starter
Yep- mine doesn't have the slightest hint of corrosion and looks new. Like you - I will replace anyway for good measure. Will check my fuel pressure before replacing the relay. What pressure should I have at the rail with a healthy system?
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10-16-2018, 06:41 PM
#8
Junior Member
Thread Starter
Thanks gents. Had 64 psi at the rails- was bummed that it was looking as if I was going to need to do more maintenance. Then I realized it hadn't started since I parked it and the pressure might be residual. Bled it and checked again with the key in the on position and also while cranking - 0 psi. Switched out the relay - boom. Just under 80 psi and fired right up. Thanks for the assist - owe you both a cold beer!
10-16-2018, 06:44 PM
#9
Junior Member
Thread Starter
Bbirdwell - I went ahead and ordered the 70A relay and 80A socket. Will follow your instructions and upgrade the relay when everything arrives this week.
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bbirdwell (10-16-2018)
10-16-2018, 09:52 PM
#11
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That’s great! Glad it worked out for you.
Mine would start religiously while at my shop or close to it. It would only decide to not start when I was far away. AMG gods haring on me. Hahaha.
Mine would start religiously while at my shop or close to it. It would only decide to not start when I was far away. AMG gods haring on me. Hahaha.
10-16-2018, 10:34 PM
#12
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Join Date: Jan 2014
Location: Republic of Texas
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'99 and '05 E55 AMG
I carry a pack that has common failure parts on the E55 to include a spare CPS and relay with the tools to replace them on the side of the road if necessary.
10-16-2018, 11:26 PM
#13
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What is your full repair kit consisting of?
10-17-2018, 11:19 AM
#14
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'99 and '05 E55 AMG
-K relay, 1 each (this is the standard fuel pump relay but will work in other positions in the front SAM)
-CPS sensor, 1 each
-CPS bolt, 8mm Torx head, 2 each (for when I drop the original under the car and lose it in the weeds)
-Camshaft sensor, 1 each
-Brake light switch, 1 each
-6" electrical tape wrapped around a pen (to tape the original CPS bolt to the Torx socket so I don't drop the bolt under the car and into the weeds)
-8mm 1/4" drive Torx socket, 1 each
-8mm Torx box-end wrench, 1 each
-1/4" drive ratchet, 1 each
-1/4" drive swivel, 1 each
-1/4" drive extension 14" long, 1 each
-Crosstip screwdriver, 1 each
-T-handle 4mm hex wrench 8" long, 1 each, for manual closure of the sunroof if it fails in the open position. Which it did for me once 500 miles from home.
-iCarSoft MBii, 1 each
-CPS sensor, 1 each
-CPS bolt, 8mm Torx head, 2 each (for when I drop the original under the car and lose it in the weeds)
-Camshaft sensor, 1 each
-Brake light switch, 1 each
-6" electrical tape wrapped around a pen (to tape the original CPS bolt to the Torx socket so I don't drop the bolt under the car and into the weeds)
-8mm 1/4" drive Torx socket, 1 each
-8mm Torx box-end wrench, 1 each
-1/4" drive ratchet, 1 each
-1/4" drive swivel, 1 each
-1/4" drive extension 14" long, 1 each
-Crosstip screwdriver, 1 each
-T-handle 4mm hex wrench 8" long, 1 each, for manual closure of the sunroof if it fails in the open position. Which it did for me once 500 miles from home.
-iCarSoft MBii, 1 each
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tw2 (10-17-2018)
