Uneven Injector Output ***Split from PPR Shim Source ***

[David T]

While it "looks" correct, can't tell from the picture if it comes with the necessary fittings to connect to the Delorean version of the K-Jet system. The description mentions an auxiliary kit of adapters. You may need it.

[bytes311]

So I received my KJet tools in the mail yesterday. I hooked it up in line between the FD (top post) and the large bolt on the WUR with the valve positioned on the WUR side.

I closed the valve and jumpered my RPM relay to test Primary Pressure. My first reading was 25 PSI. That didn't seem right, so I disconnected and reconnected the jumper wire and saw the gauge rise to about 45 PSI. Very low reading according to the workshop manual.

I then tested my Control Pressure. I re-installed the RPM relay, opened the valve and started the engine. Cold, it started off low, but then it quickly elevated to about 3.3-3.4 bar, so about 47 PSI. I blipped the throttle and the pressure dipped and recovered. That seemed normal.

I found some washers in my toolbox and decided to shim my PPR spring to get Primary Pressure up to 70-75 PSI. For some reason it would only go up to 65 PSI. I figured that's better than what it was, so I fired up the engine. My Control Pressure jumped to 80 PSI constant. I shut the engine off and started it up again. Same result, 80 PSI.

So, now I'm wondering if my my FD and WUR (both refurb by the PO from the same company at presumably the same time) are calibrated together for good Control Pressure at 45 PSI Primary Pressure? Or does that not make sense at all? I don't know anymore. I'll also add that I blew air through the inlets on the WUR and it blew out clean.

[Ron]

No, they can't be calibrated like that.
If I'm reading correctly, something doesn't add up here -- You can't have 80 psi Control pressure unless there is at least 80 psi Primary pressure, because the WUR/CPR bleeds off Primary pressure to obtain the Control pressure...

[MikeWard]

Can you do me a favour and post some pictures of the pressure test kit as you have it setup on the car?

I was assisting a fellow US owner a couple of weeks ago and he had a similar issue with erroneous readings, and it came down to a connection on the pressure tester he was using.

[bytes311]

No, they can't be calibrated like that.
If I'm reading correctly, something doesn't add up here -- You can't have 80 psi control pressure unless there is at least 80 psi Primary pressure, because the WUR/CPR bleeds off primary pressure to obtain the control pressure...

That's what has me confused. My Primary Pressure is topped out at approx. 64 PSI.

20190506_185136.jpg

I can confirm this with the RPM Relay jumpered and the valve on the gauge set closed. When I switch it over to read Control Pressure (valve opened and RPM relay connected and engine running) it shoots up to 80 PSI.

The Control Pressure was around 47 PSI before I added several shims to the PPR spring as shown below.

20190506_184120.jpg

[bytes311]

Can you do me a favour and post some pictures of the pressure test kit as you have it setup on the car?

I was assisting a fellow US owner a couple of weeks ago and he had a similar issue with erroneous readings, and it came down to a connection on the pressure tester he was using.

20190506_173338.jpg

I'm at work right now but I took this picture of my setup from last night.

[Ron]

Have you checked the both with the engine running since shimming?

[bytes311]

Have you checked the both with the engine running since shimming?

No, just the Control Pressure. I didn't check Primary Pressure with the engine running.

[Ron]

I looks like you have the original line from the FD to WUR/CPR still hooked up in the pic??

[bytes311]

I looks like you have the original line from the FD to WUR/CPR still hooked up in the pic??

Correct. The kit came with banjo bolt fittings. Did I hook it up wrong?

20190506_093000.jpg