Question about timing...

General Bellett, Gemini 75-98, Piazza 81-93, Bellel, Florian, 117 Coupe, Minx, Aska technical discussion.
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wedgenut
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Post by wedgenut »

Don't get me confused with your valve cover nonsense, it has taken me years to get to cam cover from rocker cover!!! I'll try and explain it all a bit better. If you have the pulley notch lined up with "0" then no"s 1 and 4 WILL be at top dead centre, so no probing (anal or otherwise) is really required. If your valve timing has been done correctly the little mark on the camshaft wheel will line up with the notch in the tin back plate at 12 o' clock. That will be TDC on 4 and the valves on 4 should both have clearance. If the mark isn't lined up and the valves don't have clearance then you are at TDC on 1 so turn the engine one more revolution until back to zero and the cam mark IS lined up. So assuming that is all OK you can concentrate on checking dizzy position. The rotor part with the metal contact is the pointy end for this discussion and it should be pointing to the no 4 contact point in the cap or at around 10 o'clock position if you prefer. If it isn't and you are sure you ARE at TDC on 4 then you need to reset the dizzy shaft gear. Now where the small end of the shaft goes in to the head casting, on top there is a small raised area shaped like a "U" on its side as in the picture. On the dizzy shaft there isn't a line of any kind. It is a small circular indentation similar to a centre punch mark and that should be in alignment with the round end of this raised "U" section. If it isn't lined up then pull it back until the gear comes out of mesh with the cam, (you will notice it rotates as it comes back so you need to have it out of alignment by one tooth so that when it rotates going back in it does line up). It is quite obvious when it is correct. If I've lost you anywhere consider setting up a skype video link with me and I'll shout at you as you do it.

And for your information a Fender is not a fender, it is a guard down our way and a wing in the UK. Now if you ever meet an Australian or NZ or for that matter a British woman with a very attractive rear end, whatever you do DO NOT say you like her fanny, not unless you get free dental!
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Post by Bugle »

They have to call it a valve cover, because for some reason they call sills 'rockers', and those plastic strips along the sills on a Piazza are therefore called 'rocker covers' :rolleyes:

Also that thing at the bottom of the engine is a sump, not an oil pan, an oil pan is what you put under the sump when you wanna change the oil!
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Post by wedgenut »

Well done Bugo, wedgo here. We had better not get started on the cross translations between NIZLED and OZ. What you guys call a thong doesn't go on your feet over here, it goes in an entirely different place :yawinkle:
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Post by impulsive »

OK boys, got the car timed and she starts. The timing is good. But I am having a problem where it will start and rev all the way up to 3500 and stay there. Sometimes it will just start and immediately die. I have fiddled with the idle set screw and the timing and it doesn't change anything. It is my feeling this is air related or sensor/switch related. At this point though I am stuck as I do not know what to do to get it to run right and stay idling. When it is running at 3500 it does not back down and the check engine light stays on solid.

Any ideas?

Thanks- Bart
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Post by wedgenut »

sounds like the idle air hose is split or detached somewhere, probably under the plenum. High revving is usually a major air leak. It is a bit of a mission getting under there to check it but it is the most likely cause.
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Post by impulsive »

OK, here is what I am thinking. There is no open vacuum of that size sucking air in. If that were the case, it should fire up EVERY SINGLE TIME I turn the key and idle at 3500 RPMs. Correct?

Right now, I can get it to turn on and stay on about every tenth try. So for the remaining 9 tries, the car simply turns over and immediately dies.

I am at a total loss here. I know everything is hooked up. Every single rubber hose was replaced, save for one or two that were factory hoses with check valves in them.

Could a bad engine ground cause this kind of behavior?

I also wondering if I have a fuel issue. Like when I am cranking the starter it is getting fuel but as soon as I cut it off the fuel pressure dies. I have no idea how to test for that unfortunately. And you guys know every time you want to check something on this car it means major disassembly of something.

Now, I understand I have taken everything apart and put it all back together again, so problems are to be expected, but this has me stumped.

Bart
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Post by Ghost »

I don't know much about the fuel systems in these but when I was playing with a 1980's Toyota I just pulled the fuel return line off to see if it was losing pressure when turned off.
Turned out the fuel pressure regulator was no longer regulating pressure...

Though I'm not sure if it would relate to your problems, I'm no mechanic.
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Post by wedgenut »

There is an easy fix to eliminate fule pressure question. I need to check my data but there is a wire on the fule relay you can connect to that will activate the Pump regardless of ignition setting. It is common practice to use this jumper when testing fuel Pump pressure. I should be home in a an hour or so and will post the wiring data then.

Also check that the connector on the idle air solenoid is properly connected. If it isn't you can get hard starting when cold and running too fast at idle when it does eventually start and then too rich and lumpy when it warms up.
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Post by wedgenut »

Righto, if you look at the fuel Pump relay one of the wires going in the back is Black with a red tracer (or should be). If you apply 12V+ direct to that wire by probing in the back of the relay the fuel Pump will run and stay running for as long as it is connected. If you were to fit a pressure gauge on a tee piece on the fuel line you could check the static pressure. If you then start the car you can check the running pressure. But at least if you give it direct voltage it takes away the issue of it being affected by ignition operation.
Remember, only do one thing at a time. If you are confident your timing is correct then don't touch it again. If you have all the wires and hoses in the right place and you are getting a reliable spark it should run. If it doesn't then you need to follow the correct diagnostic steps eliminating possible causes one at a time.
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Post by impulsive »

Thanks, guys. Yeah, I've been thinking about fuel. The previous owner installed an aftermarket FPR in there, have a look:

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That's the Bosch FPR laying on the battery tray.

What's killing me is the inconsistency of the problem. Someone on the Zone suggested spraying starter fluid into the intake while trying to start the car to see if starts. That's pretty easy so I might give that a try and see what it does.

The injectors I installed were NOS Isuzu Injectors, looked great, new out of the box, so I can't imagine I have an injector issue.

Sitting here at work is making me crazy, I want to go home and get to work on it!

Bart
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Post by wedgenut »

I do feel sorry for you, it is damned annoying when things like this happen with no clear cut reason. I am happy to help if I can but it means doing all the basic steps one by one. To fix hard starting and erratic running there are a whole raft of things to check both electrical and fuel related. Typically it is practice to eliminate all the electrical issues as they are less prone to variance. In other words they are either good or bad. So all wiring and connectors related to starting which are Dropping resistor, injector plugs and wires, TPS and fuel cut wiring and connectors etc. If good then move on to fuel delivery. It starts with fuel Pump, fuel filter, FPR, AFM, IAC, VSV, EGR O2 sensor and all hose routing and condition. Be careful with engine start. If you have everything right it should start and run. If you don't engine start is not going to make things better. I know I have mentioned it before but please double check the large hose from the throttle body that runs down to the IAC and the hose from the other side of the IAC back up to under the plenum. The symptoms you have are exactly what happens when this hose is disconnected or split or the IAC is not operating correctly, ie not opening/closing or seized open/closed. If one of the hose connections is off or leaking you WON"T hear it as an air leak. It is in a shit of a place and hard to reach and even harder to see but a small mirror and a torch and inspection from above and under the car should help.

Do you have a factory manual? It is a big help in the diagnostics process.
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Post by impulsive »

Damnit wedgenut, its a flashlight, not a "torch". LOL.

Anyway, thanks and yeah, I know I have my work cut out for me. And yes, I have a factory manual. There's just a lot of stuff I guess I don't understand well enough to sort out without explicit instructions. It doesn't help that I have no one local who knows cars to help either.

I thought about this today, could the turbo BOV (blow off valve) get stuck open and suck air into the plenum? I was thinking maybe that could do it. I will try to get under there and see if those hoses are messed up. I did feel under there yesterday and I did not feel anything loose or outta whack. I have a few more ideas to try tonight. I know its probably just one simple thing giving me this huge headache.

Thanks- Bart
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Post by wedgenut »

regret to inform you it is a TORCH. A flashlight is something sitting on top of a black and white thing that makes wailing noises in your rear view mirror. Of course in my Piazza they are usually too far back to see or hear anything.

Re the BOV. They don't need this sort of toy to start and run well so if in doubt about it take it off meantime until you get things sorted.
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Post by impulsive »

Wedge, I have one glaring question that I have yet to find the answer too. How the hell do I read the CEL codes on these cars? With my Trooper, I would jump the A and B terminals on the diagnostics connector, and then when I turn the key to the 'ON' position, it would flash the CEL and I could count flashes to get the codes. I think it is roughly the same in the Impulse, but where do I do it?

The manual is a little vague, as it describes three connectors to check the CEL codes but does not specify what is what.

:sad1:

Bart
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Post by wedgenut »

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