refresh951

A MAF setup cannot be completely tested until its on YOUR car. The VR setup does work well and odds are that something other than the MAF is the cause. We know this from tons of experience. I think it is irresponsible to throw around these accusations unless you can prove it is a faulty product and just saying the car is pristine is not enough. These cars are 30 years old.

schip43

Pretty sure most of us tend to agree. These are "old cars, with old electronics and wiring harness! Crap is bound to happen ... don't shoot the messenger as it were. .

jimbo1111

I think you missed the point where I reverted back to afm and the car operates as the factory intended. So continued discussion should be surrounded around the maf not operating correctly. Or its more sensitive to slight variation than an afm. Or it needs tweeting to get it to work right. So please lets get this , its the cars fault out of the equation. Than the discussion can be more fruitful.
This is my second VR system. The first one ran flawlessly and I enjoyed it for many years. This newer setup is very different and I'm sure probably improved over the years. I'm not happy with the idle its providing. Besides this the car runs strong.


Also the system is brand new. It was sourced all from one place including the injectors.

V2Rocket

... but did you adjust the idle screw?

The MAF and ECU still must work with the rest of the plumbing.

jimbo1111

Im trying to get the idle dialed in as best as possible before I install the new JME cam I purchased. FYI, if your looking for the best cam money can buy. He only has 3 billets left. Then he is off to retirement and history. His cams alone are worth about 50 hp at the same boost levels. Work of art. Johns stuff is awesome too but he better get this sorted out..

refresh951

I get the point. Do you know how many guys have stated this exactly like you did and it was not the MAF? The MAF setup requires proper operation of several things that do not matter as much with an AFM.

jimbo1111

It seems like a common issue like in this FS ad. https://www.ebay.com/itm/porsche-944....c100033.m2042
Im not going to give up just yet because I really would like for it to work. I"m going to go over everything once more and see what happens. If you have any recommendations where and what to look for LMK thanks.

shortyboy

What are the mods on your car, so that we all can get a better idea of your setup. Are you on the stock cycling valve and Wastegate? You mention injectors, do you you have lo impedance or high impedance injectors? If high impedance, do you have the proper rated resistors installed to be used on the factory dme? I get your point, regarding factory working properly, but with all performance mods, it takes a bit of adjustment to make it work properly. That's why we're all here to help.

jimbo1111

The vehicle is completely stock. Only mod besides the VR MAF is an MBC. The injectors are I believe the 80lb high impedance injectors. I made it clear to John that I didn't want to hack the wiring. So no resistors are installed.

V2Rocket

ok, what is going on with the idle that you don't like?
let's start there.

jimbo1111

Engine Idle is low on startup and sometimes misfires around 750 rpm. When the engine warms up the idle drops and hovers around 600 rpms. Startup when the engine is warm is difficult and must be done with adding fuel with the accelerator. Driving there is a hiccup off idle. The car drives fine off idle all the way to redline.
Funny thing is that I can smell fuel at idle from the exhaust. So it may be rich but I cant be sure because I currently don't have a way of measuring via a WB. In my mind those two situation rich and low idle point me too the injectors not delivering fuel properly.

V2Rocket

What happens if you screw the throttle idle bypass all the way closed?

Tom M'Guinn

You posted a link to someone selling a Rogue MAF, sold by Lindsey Racing, because he was unhappy with the idle.

You have a Vitesse MAF. They aren't the same thing, at all, fierce rivals actually.

Lindsey's limited ability to support Rogue's products is yet a further complication. To point to a Lindsey product as proof that your Vitesse MAF is flawed is just unfair and wrong.

You are arguing that McDonald's makes bad hamburgers because you once saw a guy who didn't like a Burger King Whopper he bought from a Roach Coach.

If this is really about getting help with your car, post pictures of the installation; post a video of the idle; tell us what you did to set the idle; post the MAF voltage at idle; post a log if you have one; tell us what testing you have done.

Everyone here --to a person-- wants to help, but they can't help if you don't let them.

jimbo1111

This thread has diverted from its original intent which was to see if others have used a 968 maf on a 951 application with success.
Part of the purchase of the MAF from VR. Should include some basic trouble shooting. So when I reinstall it. I will contact John and go through some trouble shooting with him. Opposed to afm the VR maf probably needs everything on the car in perfect condition and requires more work from me than I initially wanted to invest.

schip43

LO L,well I too thought it was about using the 968 MAF, but whatever. :And if you did buy a system new from VR?? LOL well of course asking him for help ... should have been your first step.

But hey that is not what you did but ... whatever . So welcome to the world where "everybody is an expert!" Which is not to say some aren't (uh not me to be sure!) But I would suggest a slight step "sideways' with figuring out what the heck is going on??? You say it's running rich at idle and you can smell fuel?? Well that tell's something ie to much fuel at idle but how rich is to rich?? if you can smell fuel, it can't be 14.7 but is 14 to 1, 13 to 1 12 to 1 or richer still?? Knowing how rich it is at idle would be useful information?? And while admittedly a step sideways adding a Wide Band 02 sensor ... would be helpful! ANd it could save your motor down line cuz you know vacuum lines break and vacuum hoses pop of?? It's a thing cuz you know crap happens just a thought, good luck going forward, keep us posted..