Car not running right after upgrading to 1300cc Injectors and twin fuel pump
 

Hey guys!

Hoping someone else has had a similar problem so I can get it worked out asap.

My car went into the shop running perfect,L with no issues. I had ID 1050 Injectors and single Walbro 450 pump.

I was maxed out on fuel so as per instruction from seb at specialty z I got my car into the shop to upgrade Injectors to 1300cc and to a Cjm twin pump set up. Second pump is a Walbro 520 and is controlled with a hobb switch on it's own seperate relay.

As seb is my tuner I didn't have the shop do any tuning.. Just do the install. Upon leaving the shop my car was idling very high a 1400 rpm and also wouldn't accelerate past 2.5k rpm it would just bounce at those revs.

Seb has sent me a tune update but it hasn't changed any of the issue at this stage. Just wondering if anyone may have come across something similar and has some input to help here.

Many thanks! Merry Christmas z fam.

Hey Mike,

If you remember, my car was set up exactly as your's with 1050x injectors and a single walbro 450. I had to upgrade to 1300cc injectors and cjm's twin pump set up and added a walbro 520 also. It's controlled by a hobb switch too. The upgrades were done by another shop and then sent to Seb for tune. It ran great even before it went to Seb for tune, just on the rich side.

Sounds like the shop that did your fuel upgrade did something wrong. I'm sure Seb should be able to tell you what to go back and check. I guess a good place to start would be fuel pressure. What does your gauge read?

Maybe have a vacuum leak; as your upper plenum was removed during the installation of injectors ... hopefully something simple :ugh2:

Thank you guys! I'll check both the fuel pressure and the vaccuum hose and see if that's it ����

Still having trouble with this.

Car went back to the shop to get it sorted. They said it was fixed and to come pick it up. After around 30 seconds of driving it was back to idling high (13-1400 rpm) and not going past 2500rpm (limp mode). The shop said they had checked over everything and did a smoke test to check any leaks and it was fine. They then checked the data and think it's to do with the tune, although I have seb from specialty Z taking care of that and he doesn't see anything in the tune to be causing it. It's really hard going back and forth between a shop and a tuner. Especially when my own knowledge is limited already.

I'm looking to try and trouble shoot this then knock things down one at a time to get it sorted.

To recap, car went into the shop perfectly fine. Injectors got upgraded from 1050 to 1300.

Fuel pump got swapped to twin pumps with a hobb switch.

What could possibly happen in this install that would be getting the car to run this way and go into what seems to be limp mode? I really don't want it have to take it back to the shop yet another time as it's a huge hassle to do so.

Any ideas of what to start checking through?

Also if it helps. When I picked up the car the first time after the install. All these codes were up. Not sure what they are but. Maybe someone with more knowledge can recognise if one one will relate to the problem

Rip everything out and re install it.