Engine running rich - suspect connections?

Ped

Club Member
So the Zed has been out and about recently and runs OK. However it is running rich and can seem to be over fueling when starting up from hot. I have a workshop manual and it recommends checking for vacuum leeks and poor electrical connections first.

So I am going to go round and check all the relevant connections and clean them up.

What do you guys use on electrical connectors? I came across 'DeoxIT Contact Cleaning Fluid'. Any other good products anyone can suggest?
 

niroshann

Club Member
Used a similar product myself. Decided to plug and unplug connectors a few times to ensure it worked its magic.
 

Ped

Club Member
Have had a quick look at the wiring in the Zed. There are a couple of plugs that are just sitting loosely on their connectors with the wire clips missing, that's not ideal. So have decided to start there.

The Thermotime Switch plug is missing its clip, looks really brittle and is damaged, plus the rubber boot is crispy too. It is a bit vague when you disconnect and reconnect it.

thremotime_switch_280zx.jpg


As you can see the connector next to it has been replaced. This was done when I put it in to a ‘specialist’ last year to try and get it running better. They replaced the connector right next to it, but left that old one loosely in place. Not ideal surely? Probably left it as there is not enough wire to chop off and replace the connector easily.

Anyway, I have decided to replace the Thermotime Switch ‘harness’. It’s only about 8” long and has 2 wires. Have ordered up the bits to do it as the replacement one I saw online was $74.99!

I already have the correct crimping tool and correct cable from the mirror conversion I did a while back.

There is another plug with no retaining clip, just sitting loosely on the Cold Start Valve. Have ordered a new plug and boot for that too, but will see how I get on with the other ‘harness’ first before copping bits off.

cold_start_valve_280zx.jpg


No point in cleaning other bits first until I get the obvious stuff sorted.
 
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uk66fastback

Club Member
These things get SO brittle with age. It can be a nightmare going through these connectors, opening them up etc, they just snap and break (or just disintegrate) ...

You need to go through these making them as good as possible as you go I think ...
 

Ped

Club Member
These things get SO brittle with age. It can be a nightmare going through these connectors, opening them up etc, they just snap and break (or just disintegrate) ...

You need to go through these making them as good as possible as you go I think ...

Hoping I have sourced the correct replacement connectors, but until I get them in my hands I wont know for sure. Agree trying to open them up will result in a pile of crumbs.
 

Ped

Club Member
Connectors arrived today, so have dummied up the new 'harness' ready to test fit. Will transfer the protective sleeve from the old one once I have test fitted the new. I can the add the rubber insulators to the bullets (will need to chop off the new ones first!), oh well I have spares. The connectors look a good match and seat full. The retaining clip is much better. Only thing I need to see is how long the connectors are overall.

connectors.jpg


connector_made_up.jpg
 
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Ped

Club Member
Have now replaced the thermotime switch connector.

I went for 8amp cable: 14 core / 0.29mm wire. It seemed the best match compared to the old wire which was: 11 core / 0.30mm.

The next cable size down was 5amp 9 core/0.29mm, so decided that may be too thin?

As you can see the new connector is deeper overall, by about 10mm. The new connector has waterproof rubber seals, so that may account for some of the depth. Note: the brown one has a chunk missing off it.

old-v-new-connector.jpg



Here is the link to the parts I used (scroll down for pins):

https://www.autoelectricsupplies.co.uk/product/680/category/7

Would like to find the correct connectors for future use. I have a Bosch reference number (1287013003) I found on one of the forums, but there is only the one on eBay and it didn’t have the 90° boot, but I may order it anyway.

There must be an aftermarket one to match exactly???

The bullet connectors are a perfect replacement. Old and new side by side, here is the link:

https://www.autoelectricsupplies.co.uk/product/32

japanese_bullet_con.jpg


Here it is all made up. Made it a bit longer too:


new-harness.jpg


Fitted:

installed_plug.jpg
 
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Ped

Club Member
As usual... much, much later I finally changed the cold start connector to a new one. The old one was crusty and missing the spring clip, so just sat loose. The pins were a bit worn too.

So, I have now tracked down a good match to the OEM fitted plug/connector.

I had put this off, as when I looked ages ago, you needed a minimum order value of £12 + P&P or so to get the right connector. As I only need one, it seemed a lot. They also do a quick release version:

https://polevolt.co.uk/acatalog/J.T...release-clip.-Black.-2-way.-20900.html#SID=52

These are now appearing on ebay cheap enough at £6.35 delivered. I got this Durite Junior Timer Connector... Note: it comes with 2 sets of connectors depending on wire gauge. As it happened I had a spare 90° boot which was handy.

jt_connector1.jpg

jt_connector2.jpg


Here is the old connector with boot removed, it was knackered...

jt_connector3.jpg


New terminals crimped on... (Yes, I did remember to fit the boot before adding new terminals!)

jt_connector4.jpg


It has been bugging me for ages, the old plug was loose and crusty, so it is now all sorted.

jt_connector5.jpg


Note: the only difference I can see between old and new type is how far out the connectors stick up from the base. However, they seemed to seat fine on the old housing. It does not look like the old pins would fit in the new housing as they are a different pattern and worn, hence why I cut mine off.
jt_vs_original.jpg
 
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Huw

Club Member
I like the idea of the quick release clips. Did you try any for clearance on the sockets?
 

Ped

Club Member
I like the idea of the quick release clips. Did you try any for clearance on the sockets?
The quick release version would have fitted on the cold start no bother, it is just that on ebay the only quick release ones have the extended sealed back to allow for grommets. This would have stuck up a bit far IMO. The link to Polevolt above has the short body one I would have gone for (other than the minimum order issue).
 

Huw

Club Member
The quick release version would have fitted on the cold start no bother, it is just that on ebay the only quick release ones have the extended sealed back to allow for grommets. This would have stuck up a bit far IMO. The link to Polevolt above has the short body one I would have gone for (other than the minimum order issue).

I’m going to put an order in with Polevolt for those connectors to replace my injector connectors. If you want anything drop me a pm.

Huw
 

Ped

Club Member
I’m going to put an order in with Polevolt for those connectors to replace my injector connectors. If you want anything drop me a pm.

Huw
Thanks Huw, but I'm pretty much sorted or now thanks. NB: I think you meed to order each item separately from Polevolt, ie: terminals, rubber boots and connectors.
 
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