Northstar Engines and System Technical Discussion Discussion, Jury rigged solution in Cadillac Engine Discussion; To the older OBD 2 boys issues with the speed limiter. Ie, the 112 gov for some of us very ...
- 03-10-04 05:43 PM #1
Jury rigged solution
To the older OBD 2 boys issues with the speed limiter. Ie, the 112 gov for some of us very poor schlubs, etc. I talked with a guy at Cadillac, the first ever who was helpful and interested. The governor engages with a "Fuel Cut-off Engaged message." It does so by ungrounding the fuel pump. He said that by regrounding it with a seond little fuel pump relay circuit, you can cheap shot your way past it. It will throw a check engine light, but will still work properly. I'm going to get that done as well with my heads (which will still be a while) and see how well it works. Woot!
- 03-10-04 11:23 PM #2
Re: Jury rigged solutionOriginally Posted by ShadowLvr400
Dude, I don't know who you talked to but I think you got some bad info....the speed limiter does not work by shutting off the fuel pump..... That would be a quick way to damage the engine causing it to run momentarily lean. Never would that be an acceptable solution. The speed limiter acts on the injectors, interrupting the injector pulse width. You cannot override that with a relay. This is pretty easy for you to check out yourself if you disbelieve...put a fuel pressure gauge on the fuel rail fitting and go run to the speed limiter. I'll bet you a case of pop that the fuel pressure stays constant. If the pump was being shut down to limit speed the fuel pressure would have to drop if it was to have an effect on the engine, right?? check your fuel pressure before you start wiring any relays in. That is why "that Cadillac guy" was so helpful....he got you to go away with bum info....LOL
- 03-11-04 08:29 AM #3Cadillac Owners Fanatic
- Automobile(s): 2001 DTS
- Join Date
- Feb 2004
Re: Jury rigged solution
So how can it be defeated. I have a 98 Deville and though it is not really a issue I would love to know I could go faster if I needed to. Mine has the S rating on the door so I'm thinking 110mph is about it am I right?
- 03-11-04 09:09 AM #4
Re: Jury rigged solution
Bob, he actually said that it wasn't hitting the injector pulses, he said it was just ungrounding the pump, and that's how it took power away. If I set up a second, manual relay switch and test, how much damage you think could I do bob? (Assuming I do it right)