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B21ft no-start

Kjet injector testers are a gasoline version of a diesel injector tester. They test at much lower pressure. You test spray pattern, opening pressure and total flow. It's a hand pump operated unit. I haven't seen one in about 20 years.

Getting closer!
 
I found a diagram for all the fuel hose routing and will double check tomorrow to make sure I'm not making some simple mistake. If everything is hooked up right, which I'm confident it is, I'm going to see if our dismantler that I got my replacement fuel lines from has the compatible FD.
 
The plunger was sticking. Got a FD from our dismantler and while I had the old one out I compared the two. I didn't realize how high up the plunger lived in the FD. Put the new one in, and the car started and idled perfectly on the second attempt. Now just need to drive it and see if it makes power.
 
Well, it started and ran very smoothly, but once I took it on a short test drive and tried to get into boost I started having problems. It feels like its choking up, not making power, severe hesitation (like the car shuts off for a second then comes back). Finally figured out the WG hose was gone and it was probably making more boost than the fuel could handle. Now its more or less drivable, but still makes very little power and starts to miss after a few minutes of driving. I started to notice a hail on a tin roof sound from the front of the motor revving it at idle which I believe is pinging. So, maybe I added 87 and not 93 when I put a few gallons in the tank when I got started. Hopefully getting some octane in there will sort out the power issues, but I think there's something else going on to make it sound like its running on three cylinders once it gets hot.
 
Get the gauges from TestPoint?

Fresh plugs and bougicord wires may be a good idea.

Spray baking soda water on the wires at night and look for arcing.

Auto? Do a brake stand and see if it misses= ignition misfire is likely.
 
Haven’t gotten the gauge set up yet, I’m tempted to just buy a CIS testing kits do not have to think about it. I spend so much time working on cars making a tool is just one extra job (that I keep putting off).

Plugs are new, cables will check but looked okay, does feel like ignition to me (clears up around 4-5k).

It’s an m46 car, I could use the ebrake and load it up.
 
I have the factory gauge available to rent.

K-JetFuelPressureGauge.jpg
 
Don't forget about those spray patterns. You may be getting lots of fuel but if it isn't atomized by a good spray pattern. Then you are just dumping liquid into the cylinder which doesn't compress or burn.
 
adamdrives said:
It feels like its choking up, not making power, severe hesitation (like the car shuts off for a second then comes back).
Click to expand...
There's an over pressure safety switch (above the brake pedal IIRC) that turns off the main fuel pump relay if boost pressure gets too high. I don't know what it feels like when it triggers, but sounds like it might match your description.
 
It shuts the engine down and then when you let off it comes right back. So you would get a surging stutter if it hits that pressure switch setting. A non intercooled car only has a 9 or 10 psi switch. The intercooled cars have a 13-14psi switch.
 
So I drove her again tonight and noticed that it makes good power above 4K or so. Lugging it in first gear up to that, it feels like the brakes are on. I’m wondering if it’s possible I popped the vac advance diaphragm when I first got the car running. I can’t remember but I don’t think I installed that check valve until after I had actually gotten it out of the shop. Any other ideas? Idles poor throttle response and sounds like it’s not running on all cylinders until you get it revved up.
 
Did you check the injector spray pattern? If the fuel isn't being atomized it's difficult to ignite.

I believe the port for the vacuum advance/boost retard is right at the throttle plate.

B21FT_Evap.jpg
 
No, I have a spare set of injectors that I could get tested if I can find someone locally. When I had the injectors out they all sprayed about the same but I didn’t pay too much attention to that at the time.
 
Tested the advance diaphragm and it’s good. Could clogged injectors cause poor running at low rpm and then clear up in higher rpms? I’m sure they could use a rebuild but I would like to focus on this particular issue. There is still a metallic clanging noise at low-mid range rpm coming from the front of the motor that I thought was pinging, but with high octane it’s still present. Somehow this still feels like an ignition timing issue to me, I just don’t know what else to check.
 
Did you replace the injector seals when you checked the injectors? They fail and create a vacuum leak affecting idle and mid range the most. The intake manifold gasket also fails and causes poor running as well.

The metallic sound from the front would make me check the bushings for the alternator, and power steering. I'd also want to check the timing belt tensioner.
 
I replaced the injector seals and intake manifold gasket when I had everything off to replace the harness. Since then I’ve smoke tested the intake a few times and there are no leaks.
 
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