Otodats President

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Otodat
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Re: Otodats President

Post by Otodat » Mon Jul 22, 2019 5:18 pm

I do plan to delete the egr, thought I would leave it for now so I wasn’t second guessing it if I had issues, as I expected there would be some. Hadn’t considered removing the canister, would you get fuel smells if was removed?

Thinking about it today , speed sensor code would come up unless it was driven, checked throttle switch and it seems ok. Park/ neutral code is probably because it’s not driven.code 31 is probably irrelevant as no auxiliaries have been used (increases idle for aircond etc)

Seems that it runs ok ish when cold, but once it warms up it won’t idle and seems to miss, possibly backfire? Pulled the vacuum off the idle air control, didn’t seem to make much difference. After running, fuel pump codes no longer there, but had a code for temp sensor

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Re: Otodats President

Post by broke » Tue Jul 23, 2019 10:44 am

Sounds about right. I've deleted the charcoal canister off every daily and project I've had and never had an issue. In some cases it actually significantly improved the smoothness (less vacuum hoses to leak I guess). Just rip it all off and put an inline fuel filter off the hardline that runs back to the tank. This should also stop the whooshing noise when you open the fuel cap (every charcoal canister I've had has been blocked too).

Your hot running issue sounds a lot like a bad coolant temp sensor. I also had this on the Laurel, it was actually partly the wiring to the sensor too. When hot, wiggling the sensor wiring made the car intermittently run like arse. I suggest if you replace the sensor to get a new plug and redo the wiring as far back as you can be bothered, the heat from the engine seems to make them quite brittle.

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Re: Otodats President

Post by Otodat » Sat Aug 03, 2019 3:50 pm

180bst came down last weekend for a look, checked over a few things. Temp sensor sitting at 3.94kohms when cold and seems to get lower when as it warms, 5 volts on lead. Checked idle switch (tps) seems ok. Pulled a lead and put on a spare spark plug, getting consistent spark Turing engine over. Had a listen to an injector, heard it ticking turning over. Suggested checking fuel pressure so I ordered a gauge, sitting at 35psi. Checked airflow meter output, 4.8v ramps down to 0.6v fully open. Things seem to be getting worse. Just stumbles and stops after first crank now, then turns over without firing. Suspected igniter might be dozy so took it off and threw it in the freezer for a couple of hours, nope still the same. Had a replacement ordered which turned up this week, pulled it out of the packet and derp- ordered a different type. Long story short, no meaningful progress.

Otodat
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Re: Otodats President

Post by Otodat » Sat Aug 03, 2019 5:38 pm

Disconnected a injector lead to check voltage, when I turned it over it fired and ran (rough) for a bit. Weird.

Otodat
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Re: Otodats President

Post by Otodat » Sat Aug 03, 2019 11:20 pm

Hhmm, you would think with a system of this age there should be a resistor pack somewhere.

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Re: Otodats President

Post by 180bst » Sun Aug 04, 2019 6:57 am

Otodat wrote:Hmmm, you would think with a system of this age there should be a resistor pack somewhere.
Bugger! :? Fuel Pressure :thumbsup:
I wonder,only because it seemed to be happy to run on engine start, if the replacement injectors are the same impedance as the old ones?
Although the old VG20 I am playing with has the similar style old injectors to yours when I measure them they come in at 2.5 ohms which makes the low impedance as opposed to the high impedance type that would be around the 10 ohm ish reading.
Not knowing anything about your system..wish there was a service manual!
With the eccs system its running there is NO external resistor in the circuit so must be some hi current switching ability in the ecu. If you did have an external resistor block it should be easy to spot and seeing that you have had it all apart i think you would of spotted it...
1975 610 Sedan VG20ET
1973 610 SSS Coupe
1983 C20 Van
1981 720 Cab Chassis

Otodat
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Re: Otodats President

Post by Otodat » Sun Aug 04, 2019 8:09 am

These are 2.5 ohm injectors also, measured an old one at 2.7 ohm. Yeah you’re right I would have seen a resistor block if it had one. Gut feeling that there some sort of power or earthing issue. Have a module in the engine bay A18 800 030 that I’m not sure what it does. As near as I can figure from an internet search it is fuel temp driver, but this doesn’t seem right as there is no temp sensor I can see on the fuel system. Anyway a fuse for it was blown, replaced the fuse and it’s still ok.

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Re: Otodats President

Post by 180bst » Sun Aug 04, 2019 8:23 am

Yeah maybe power issues... check the 12v supply on the injectors when cranking see how thats performing.
1975 610 Sedan VG20ET
1973 610 SSS Coupe
1983 C20 Van
1981 720 Cab Chassis

Otodat
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Re: Otodats President

Post by Otodat » Sun Aug 04, 2019 10:29 am

Backprobed the ecu power and hooked up a jumper cable from the battery- fired straight up and ran perfect. Image
Then noticed I hadn’t hooked up one of the injectors. Stopped it, hooked it up- runs but won’t rev up properly. It’s almost like the injectors are pulling too much power. Which makes me think the impedance isn’t right [emoji30]

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Re: Otodats President

Post by Otodat » Tue Aug 06, 2019 5:15 pm

This is at a point where it can be driven. Took it out and gave the floor a sweep then had a reshuffle. Feels good to claim some space back.Image

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