Delete Fuel Shutoff Solenoid without getting a P0215? - PeachParts Mercedes-Benz Forum

777funk · #1 05-15-2025, 08:20 PM

A place called Benz Injection sells a blockoff plate that deletes the fuel shutoff solenoid. It seemed to make sense to a certain extent (less leak points for air getting into the system and the rack shuts off anyways).

But... once done, it's been sort of regretful. The rack does shutoff but there's a surge when shutting down. It almost sounds like a runaway for a second.

The real issue though is that now there's a P0215 and the car will not be able to pass emissions since this is a CEL code. Is there a way to stop this from happening besides putting the solenoid back on?

777funk · #2 05-16-2025, 03:05 PM

bump

multicast · #3 05-20-2025, 09:21 PM

I have the exact same SOV delete from Benz Injection. So a few things about the delete:

It's totally normal that there is a short surge in RPM when you remove the SOV. The reason for this is because the SOV is what diverts the fuel from the injection pump back to the fuel pump suction side. The reason for this is because you have a mechanical fuel pump that is still pumping fuel so to avoid a pressure issue the SOV loops the fuel circuit and shuts the valve going to the injection pump. This is why the engine shuts down so quickly with the SOV. When the SOV is deleted the engine relies on the injection pump de-energize function to shutdown the engine. The quick surge in RPM that happens right before shutdown is because part of the injection pump shutdown moves the rack in the injection pump slightly forward before pulling it all the way back to the "closed" position which is what shuts off the engine. This is totally normal and expected.

The SOV code you're getting... Well that one is more complicated. Benz Injection sells a Sean Treacy Stage 1.5 tuned ECU which boosts performance, and one of its other benefits is that it deletes a few things out of the ECU such as EGR/MAF/SOV. I've been speaking to Sean and Benz Injection (Shane) about this very issue and it seems that the Sean Treacy ECU's that are in the USA don't actually delete the SOV out of the software, only the European ECU's had the SOV deleted. Sean has acknowledged this issue and is working on getting an update sent to Shane at Benz Injection to test to make sure this issue is resolved for all USA ECU's. The ETA they gave me for this is 2 weeks so hopefully soon we'll have a fix.

Hope that helps!

multicast · #4 06-02-2025, 05:34 PM

BenzInjection/Shane sent me the new Sean Treacy ECU today and it resolves the SOV CEL issue. So for those of you that want to delete the SOV and greatly improve your fuel system with the BenzInjection SOV delete plate you can do so now without any issues!

BenzInjection.com is awesome so if you're ever looking for parts I can't recommend him enough. When I first reached out to him he got me in touch directly with Sean and he worked with Sean to get my ECU issue resolved and didn't even have me pay for return shipping!

He stands behind everything he sells which is just great.

777funk · #5 06-02-2025, 06:23 PM

Quote:

Originally Posted by multicast

BenzInjection/Shane sent me the new Sean Treacy ECU today and it resolves the SOV CEL issue. So for those of you that want to delete the SOV and greatly improve your fuel system with the BenzInjection SOV delete plate you can do so now without any issues!

BenzInjection.com is awesome so if you're ever looking for parts I can't recommend him enough. When I first reached out to him he got me in touch directly with Sean and he worked with Sean to get my ECU issue resolved and didn't even have me pay for return shipping!

He stands behind everything he sells which is just great.

I don't think it mentioned that a different ECU needed to be used to get it to work. Also, I emailed his company after buying this plate regarding a small complaint. He recommends using 3/8" fuel hose over the top of the old fuel lines which are to be cut off and hose placed over. His Shutoff Valve delete plate comes with a 1/4" fuel line banjo fitting. So now it's necessary to adapt from 3/8" hose everywhere else to a 1/4" line to feed the IP through his plate. I suggested politely that he should change the banjo to barb fitting to 3/8" hose and never heard anything back. I would have expected at least a thank you for your concern email. Really to do it all over again, I would recommend against this mod. Not worth the effort and cost.

multicast · #6 06-03-2025, 12:06 AM

Quote:

Originally Posted by 777funk

I don't think it mentioned that a different ECU needed to be used to get it to work. Also, I emailed his company after buying this plate regarding a small complaint. He recommends using 3/8" fuel hose over the top of the old fuel lines which are to be cut off and hose placed over. His Shutoff Valve delete plate comes with a 1/4" fuel line banjo fitting. So now it's necessary to adapt from 3/8" hose everywhere else to a 1/4" line to feed the IP through his plate. I suggested politely that he should change the banjo to barb fitting to 3/8" hose and never heard anything back. I would have expected at least a thank you for your concern email. Really to do it all over again, I would recommend against this mod. Not worth the effort and cost.

Yea so I think it's been a learning experience for Shane/BenzInjection. He thought you could also just plug in the SOV and leave it dangling and it would resolve the issue as well but that wasn't the case. I can say with 100% certainty that changing the fuel line size won't resolve it either. The actual issue is that the ECU will immediately detect the SOV if it's not plugged in and throw a CEL or if you have it plugged in an dangling it'll detect that the engine remains running after the SOV shutoff command is issued when you turn off the car and it'll throw a CEL the very next time you start the car.

At the end of the day the *only* fix to this is to get a tuned ECU that has the SOV deleted. If you're going to delete the SOV you have no choice. Now that being said I *love* the Sean Treacy tuned SOV. It also allowed me to delete the EGR and made it so I could change the EIS/Key if mine ever failed without any issue as it removes the immobilizer function plus it gets far better performance in the mid range so it's a fantastic upgrade.

I think Shane made a mistake saying that the SOV delete could be done without ECU tuning, and to be fair I don't think he knew that Sean hadn't actually deleted it out of the USA ECU's. Like I said in my post he worked with me and got the issue resolved and it didn't cost me dime.

If you aren't interested in the tuned Sean Treacy ECU then I would reach out to him and ask him to return the SOV delete plate. I think he would understand and give you a refund.

777funk · #7 06-04-2025, 08:57 PM

Quote:

Originally Posted by multicast

Yea so I think it's been a learning experience for Shane/BenzInjection. He thought you could also just plug in the SOV and leave it dangling and it would resolve the issue as well but that wasn't the case. I can say with 100% certainty that changing the fuel line size won't resolve it either. The actual issue is that the ECU will immediately detect the SOV if it's not plugged in and throw a CEL or if you have it plugged in an dangling it'll detect that the engine remains running after the SOV shutoff command is issued when you turn off the car and it'll throw a CEL the very next time you start the car.

At the end of the day the *only* fix to this is to get a tuned ECU that has the SOV deleted. If you're going to delete the SOV you have no choice. Now that being said I *love* the Sean Treacy tuned SOV. It also allowed me to delete the EGR and made it so I could change the EIS/Key if mine ever failed without any issue as it removes the immobilizer function plus it gets far better performance in the mid range so it's a fantastic upgrade.

I think Shane made a mistake saying that the SOV delete could be done without ECU tuning, and to be fair I don't think he knew that Sean hadn't actually deleted it out of the USA ECU's. Like I said in my post he worked with me and got the issue resolved and it didn't cost me dime.

If you aren't interested in the tuned Sean Treacy ECU then I would reach out to him and ask him to return the SOV delete plate. I think he would understand and give you a refund.

The hose barb size on the banjo fitting on the delete plate wouldn't change anything with the trouble code of course. It was just an inconvenience plumbing wise having to jump from a 3/8" fuel hose on most of the connections (as recommended) to a 1/4" size on the barb. More connections / adapters for different hose sizes equals more leak points. Not really the end of the world, but it would make more sense to use a 3/8" hose barb fitting on the delete plate banjo fitting. At the end of the day, likely, we'll just remove the plate and put the shut off valve back on and call it complete for now.