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Old 01-09-2020, 01:02 AM   #26
dl242gt
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Glad you got it running. Rolling that kjet!
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Old 01-11-2020, 05:16 PM   #27
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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.
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Old 01-11-2020, 09:45 PM   #28
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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.
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Old 01-12-2020, 03:59 PM   #29
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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.
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Old 01-12-2020, 04:05 PM   #30
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I have the factory gauge available to rent.

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Old 01-12-2020, 10:31 PM   #31
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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.
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Old 01-12-2020, 11:10 PM   #32
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It feels like its choking up, not making power, severe hesitation (like the car shuts off for a second then comes back).
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.
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Old 01-12-2020, 11:17 PM   #33
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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.
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Old 01-14-2020, 12:49 AM   #34
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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.
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Old 01-14-2020, 02:00 AM   #35
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Also, does the hose from vacuum advance go before or after the throttle blade?
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Old 01-14-2020, 02:27 AM   #36
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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.

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Old 01-14-2020, 12:33 PM   #37
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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.
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Old 01-14-2020, 02:15 PM   #38
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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.
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Old 01-14-2020, 02:25 PM   #39
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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.
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Old 01-14-2020, 09:09 PM   #40
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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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Old 01-15-2020, 12:28 AM   #41
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Just adjusted valve clearance, double checked engine timing and put a timing light on it. Seems to be working just fine. Next step get injectors tested? Could that really make low end stumble and clear up high rpm? Sorry to be repetitive.
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Old 01-15-2020, 12:33 AM   #42
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No they pretty much spray a nice cone pattern or they don't.

Did you take them out and do a spray test into jars / water bottles?

I have a pressure rig here as well...
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Folks on here don't know a good deal when they see it.
how psi stock cna support?

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Old 01-15-2020, 01:31 AM   #43
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I had them spraying into paper cups when I was trying to figure out my full flow injector issue, but I didn't look too closely. They all looked about the same, but at one point 2 of them were spraying much less, which I attributed to the faulty FD. I have a spare pair of injectors I could send out to be tested, but I just want to know if it's a plausible fix for my issue before I do. Maybe it's feasible that at lower pressures they aren't spraying as well as at higher pressures? It clears up immediately at around 4k, and is more or less un-drivable until then.
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Old 01-15-2020, 01:50 AM   #44
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So I've been searching by symptoms and came across this description (command f "poor power" and it pops right up) on the UK forums which describes exactly what I'm experiencing:

Poor Power; Poor Engine Response. [Symptoms] Symptoms: no power under 3K RPM; poor power after 3K RPM; no engine response, very slow response; will not brake-boost past 2 psi; idle fluctuation between 750-1200RPM; rough idle; engine makes loud bog noise from intake when throttle is opened and takes several seconds to respond, even in neutral. Does not seem to get terrible gas mileage, but could be better. Does not smoke white, blue or black. Spark plugs are white on the electrode and have black carbon around the face.

Suggested cause is ignition timing. Anything else that could influence timing besides the vac fitting on the distributor or engine timing?

Also, the cam pulley doesn't have any markings on it. With the crank markings lined up the markings look good on the aux pulley, and the cam looks more or less in the right position (both lobes off the bucket) but I didn't look with the valve cover off to be certain.
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Old 01-15-2020, 09:31 AM   #45
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I would need a little more precision than observing the lobe positions. The sprocket itself is marked with a divot on the outer rim which lines up exactly with the shaft keyway. The inner belt guide also has a notch in its edge at the same point, so you don't have to remove the guides to find it. But all could be deceiving if the roll pin in the camshaft doesn't engage the keyway. The pin shears.
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Old 01-15-2020, 12:38 PM   #46
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Will double check today

Last edited by adamdrives; 01-15-2020 at 12:39 PM.. Reason: Misread
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Old 01-16-2020, 02:45 AM   #47
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Alright. Engine timing is all good. I didn't realize the cam gear had a cover. I found all the marks.

I did more looking around today and found that the distributor "star wheel" was damaged while looking at the cap and rotor. One of the teeth was bent upwards and not passing by the impulse pickup. I don't know how that could have happened.

Anyway, I tried to remove the shaft to replace the star wheel, but the cross pin on the shaft wouldn't budge. I couldn't see any way to secure the dis without putting it in a vice and damaging it, so I bent the wheel roughly back into shape, which went better than expected. I was able to get it more or less in position.

With everything re-installed I was surprised to find the car ran more or less the same. This is the first time I've dealt with mechanical ignition timing, so things have been slow to take, but I think I'm getting the hang of it. At idle, the ign advance is about 10*, which I believe is about right. When you blip the throttle, the timing jumps immediately to 30+*. Is that how its supposed to be? I tried disconnecting the vac one to test the centrifical aspect of the timing advance and it works. The car still drives about the same, maybe a little better, but it feels like its breaking up/misfiring until around 3-4k (depending on throttle) when it clears up. Short of trying to find a good used dis, anything else I can check?

Also, the vida diagram showed a valve between the dis vac line and the manifold. The part number was for a one way valve. This can't be right, since the valve doesn't let vac out of the dis pod and the timing can't return back to rest. (verified this with timing light) So I took that out, but it still breaks up. My coworker thought there was supposed to be a delay valve there. That makes sense to me as a culprit for why the timing advances so quickly with a throttle blip. Am I on the right track?
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Old 01-16-2020, 08:46 AM   #48
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Quote:
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...
I did more looking around today and found that the distributor "star wheel" was damaged while looking at the cap and rotor. One of the teeth was bent upwards and not passing by the impulse pickup. I don't know how that could have happened. ...
I'll take the simple question.

I've read many times this happens when you have the cap removed and forget to secure the clips while someone cranks.
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Old 01-16-2020, 12:33 PM   #49
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^ That's what I thought.

Read this thread for what to check when the reluctor (star wheel) gets 'clipped'.

http://forums.turbobricks.com/showthread.php?t=307311
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Old 01-16-2020, 12:39 PM   #50
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Quote:
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Short of trying to find a good used dis, anything else I can check?


I have a known good spare low mile B21FT distributor for $100.
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