VIN# 16951 - August 1982 - Manual - Black Interior

[Horsebox]

Hmmmm. From the video it does sound like it runs well. What were your official emission results - can you post CO and HC?

I agree with Mike; you can only adjust the mixture properly if you are reading the exhaust gases directly. See if you can get an old Gunson Gastester.

The mixture screw can cause huge changes in fuel delivery. Treat that screw as you would another man's penis - i.e. as little as possible (assuming heterosexual!)

[Domi]

Unfortunately, I don't have the exact value of the CO, sorry.
You're right its pretty difficult to adjust that screw
You mean that kind of device? :
http://www.ebay.com/itm/GUNSONS-GASTEST ... SwmZFZmz3J

[Horsebox]

Yep exactly that will do but you can also get earlier versions that have an analogue gauge, if you prefer that.

[MikeWard]

Domi, you shouldn't be seeing a static figure, it should oscillate back and forth.
Is the engine hot when you are doing the dwell check? The O2 sensor only works once it's hot, so you're best to take the car for a 20-30 minute drive before checking the dwell.

My preferred method is to setup the mixture from O2 sensor feedback where possible. Setting up off of a exhaust gas tester will work in a pinch, but I cannot advocate those Gunson gas testers, in addition to taking an age to calibrate before you can use them, they don't yield the most accurate results in my experience. If you want to go down the route of setting it up from the exhaust emissions, then see if you can find a friendly garage who will let you use their emissions tester - Or, see if you can locate a Snap On Scan Gas for sale - these are really good, accurate units which are ready to use within 90 seconds of powering them on.

[Domi]

Yes the engine is hot when I plug the dwell and air/ratio.
I'll try to drive a few miles like this and see how it goes.
Don't forget, that the car wasn't driven for two years, so...

[Admin-bloke]

Your fuel computer may be broken if you are getting a constant 45 +/- 2 degree dwell reading or the multi meter is not connected correct.

First try and disconnect the oxygen sensor electrical connection at the blue write to the fuel computer. Take the blue wire that the oxygen sensor should connect to and connect this to a known earthpoint, like the battery negative post. The dwell reading on your metre should read 10-15 degrees.

Post your results.

P.s. re reading exhaust emissions, if your car had a catalytic converter, then the emissions results would be meaningless add the catalytic converter can reduce the CO by add much as 3 %. This is why the exhaust has sample points pre cat to take emissions readings from.

Good luck

[Domi]

The dwell is connected to earth and to the orange wire here:

aDSC_0011.jpg (583.72 KiB) Viewed 2714 times

Ok, I will try to connect the lambda wire to a negative point and will the result.
I'll do it tomorrow, otherwise the neighbors won't be happy because of the loud noise of the engine

[Admin-bloke]

You can do the test workout the engine running by removing the fuel pump relay and then applying 12v to the yellow/red wire (87b) using a wire link to the brown cable (30). This would energise the lambda relay and operate the fuel computer etc.

The fuel computer can be fixed 9 times out of 10 too:

[cis6409]

Just my 2 cents but in the second video especially , it sounds to me like the revs are a little too high for idle and also sounds like a small vac leak ..the high pitched whooshing noise - I had a similar noise and turned out be the vac pipe from the cold start valve to charcoal canister, give each of them a squeeze with your hand and see if the noise goes away ..


Just make sure the throttle spool is fully releasing back to the rear stop and that the throttle hammer up top is 'clicking' the micro switch ..

Otherwise sounds like a bad cpu if it's not oscillating or the full throttle microwswitch doesn't make the dwell go to a steady 54 , Nick sorted mine and it's running better than ever !

Good luck
Shane

[Domi]

First try and disconnect the oxygen sensor electrical connection at the blue write to the fuel computer. Take the blue wire that the oxygen sensor should connect to and connect this to a known earthpoint, like the battery negative post. The dwell reading on your metre should read 10-15 degrees.

I have connected the blue wire that should be connect to the Lambda sensor to a negative point, and it doesn't change anything.

Just my 2 cents but in the second video especially , it sounds to me like the revs are a little too high for idle and also sounds like a small vac leak ..the high pitched whooshing noise - I had a similar noise and turned out be the vac pipe from the cold start valve to charcoal canister, give each of them a squeeze with your hand and see if the noise goes away ..

I'm unable to find any leak from the red line and they're attached correctly.

Just make sure the throttle spool is fully releasing back to the rear stop and that the throttle hammer up top is 'clicking' the micro switch ..
Otherwise sounds like a bad cpu if it's not oscillating or the full throttle microwswitch doesn't make the dwell go to a steady 54 , Nick sorted mine and it's running better than ever !

Yes, the two screw were misaligned and the micro switch wasn't able to be fully open.
Now this is good.

So, I made another video and i thought it was fine...
Nevertheless, 31 minutes later another thing happen, the iddle goes to 1500rpm a few seconds and then go down to 900rpm
For now, I stopped the investigation, I will try this week-end...
Video will be posted once they're ready on YouTube.
Thanks again for your help