Hard Starts After Replacing Intake Manifold
Thread Starter
Super Member
Joined: Jul 2015
Posts: 795
Likes: 189
From: San Diego, CA
2016 E350 Sport; Mom Wrecked the 2008 E350; sold the 2002 C320
Hard Starts After Replacing Intake Manifold
Hello everyone,
I need a little help diagnosing intermittent hard starts after the following repairs & maintenance this weekend on my 2008 E350 Sport:
Replaced intake manifold (new Pierburg)
Replaced injector O-rings
Replaced all 4 camshaft magnets
Replaced centrifuge cover
Replaced cam plugs
Replaced expansion plug
Replaced O-rings on cam sensors
Replaced knock sensors
Cleaned MAF
Cleaned throttle body
New air filters
I finished all the work late Saturday night and didn't start the car. On Sunday morning, I went to crank it up and it started immediately with no issues - I went for a 10 min test drive with no issues. Later in the day, it again started fine. Took the family out to eat and when leaving the restaurant, I had to crank it 3 or 4 times before it started. I went for a long drive (~20 miles). I parked the car and let it sit for about 20 minutes. Then it went through a couple of long crank cycles before it started. I parked at home for a few hours, then fired up the car a couple more times and it started without issues.
This morning, it again started without issues but when I went to start it this afternoon, it started right away, but at a very low idle and the accelerator was non-responsive (while still in Park). After about 15-20 seconds it stalled out, but started normally right away when I cranked it again. However while driving, it felt I had to step on the pedal more than usual for acceleration.
It has not triggered a CEL. I suspected maybe the fuel rail hadn't pressurized yet, but I think it's ran long enough to be an issue. I popped the top covers and I do not see/hear any fuel or air leaks.
Anyone have any thoughts? Any and all duly appreciated.
I need a little help diagnosing intermittent hard starts after the following repairs & maintenance this weekend on my 2008 E350 Sport:
Replaced intake manifold (new Pierburg)
Replaced injector O-rings
Replaced all 4 camshaft magnets
Replaced centrifuge cover
Replaced cam plugs
Replaced expansion plug
Replaced O-rings on cam sensors
Replaced knock sensors
Cleaned MAF
Cleaned throttle body
New air filters
I finished all the work late Saturday night and didn't start the car. On Sunday morning, I went to crank it up and it started immediately with no issues - I went for a 10 min test drive with no issues. Later in the day, it again started fine. Took the family out to eat and when leaving the restaurant, I had to crank it 3 or 4 times before it started. I went for a long drive (~20 miles). I parked the car and let it sit for about 20 minutes. Then it went through a couple of long crank cycles before it started. I parked at home for a few hours, then fired up the car a couple more times and it started without issues.
This morning, it again started without issues but when I went to start it this afternoon, it started right away, but at a very low idle and the accelerator was non-responsive (while still in Park). After about 15-20 seconds it stalled out, but started normally right away when I cranked it again. However while driving, it felt I had to step on the pedal more than usual for acceleration.
It has not triggered a CEL. I suspected maybe the fuel rail hadn't pressurized yet, but I think it's ran long enough to be an issue. I popped the top covers and I do not see/hear any fuel or air leaks.
Anyone have any thoughts? Any and all duly appreciated.
Last edited by EuroDriverSD; Mar 14, 2017 at 01:40 PM.
Thread Starter
Super Member
Joined: Jul 2015
Posts: 795
Likes: 189
From: San Diego, CA
2016 E350 Sport; Mom Wrecked the 2008 E350; sold the 2002 C320
Thanks Konigstiger, I did double-check the seal at the rear of the engine cover and it appears to be seated fine. I have the car at the shop right now for some suspension work and when I got there, the car had a really hard time starting up again. The wrench took a quick look at it; he thinks it may be an issue with one of the diaphragms on the new intake. He's going to look into it further - I'll post any findings.
Thread Starter
Super Member
Joined: Jul 2015
Posts: 795
Likes: 189
From: San Diego, CA
2016 E350 Sport; Mom Wrecked the 2008 E350; sold the 2002 C320
Ok, thought I'd update the thread. Just picked the car up from the shop. There was a short in the throttle body. They also found that the pressure sensor the dealership sold me was not the correct one for my vehicle.
Apparently also needed a software update due to the updated cam magnets.
Expensive trip but car starts up right away now
Apparently also needed a software update due to the updated cam magnets.
Expensive trip but car starts up right away now
Last edited by EuroDriverSD; Mar 21, 2017 at 08:22 PM.
