# 1986.5 4x4 D21 issues



## 4x4body (Nov 10, 2010)

First of all I'm new to the forum, I've been a Nissan factory technician for a year and a half now; and I just bought an 86.5 D21 to use basically as my toy. I plan to take it off road, but be streetable as well, I will be buying a house soon so I need my truck to carry things. Luckily I have a second car because this truck is all kinds of screwed up.
When I bought the truck, (z24i engine) it had a motorcraft carburetor on it, and an old distributor with points to make it run. I replace the carb with a throttle body that I got from a used truck, also a used dizzy, a rebuilt ecm, and put it all together. After all that, the exhaust coil was not firing until last night I had a bad power transistor. 
The problem I have now is electrical, harness or sensor related I believe. Saturday I drove my truck home from work, got about 10 miles and it cut out. I was on the highway so I kept rolling, intermittently it would fire again, just enough to pretty much keep me going at about 40mph.
Sunday I put a new cap and rotor on it since the distributor was used, it made a world of difference. The truck started right up, idled fine, drove it for a few miles and it cut out on me, it had done that to me the day before which is why I replaced the cap and rotor. I'm not sure if it is cutting ignition or fuel during its "hiccups", but thanks to it cutting out I spent about 5 minutes to move 20 feet!
I used a spark tester and now it has spark at both intake and exhaust side spark plugs, I can see a spray pattern on the throttle plate from both injectors. I tore my harness apart to inspect the splices as I had seen elsewhere in this forum. I am thinking that my mass air flow sensor is a problem to investigate.


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## dvdswanson (Nov 6, 2005)

hows the fuel pressure? remember you went from carb to injected and welcome to the forum.


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## 4x4body (Nov 10, 2010)

The fuel line was teed at the inlet to the return to drop pressure for the carb. Fuel pressure was measured at 32 psi, specification is 36, which should be close enough to not be the problem I'm hunting.


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## hoots007 (Sep 23, 2010)

Hey folks new to this also (first post) Got an imported japanese 1989 2.7 crew cab d21 (4 door) need a translation for the fuse box..Keeps blowing one fuse but I can't seem to find whats blowing, nothing obvious..Sorry for jumping in...any help much appreciated...cheers


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## 4x4body (Nov 10, 2010)

Hoots, I'm not sure if the jdm has the same fuse box as the usdm, you should be able to find a diagram for the usdm. I would also appreciate you not hijacking my thread in the future. If you can't find a diagram pm me and ill get you one but it would be for a usdm


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## saudade (Apr 10, 2010)

Do you have access to parts to try out? If so, then the MAF is a good suspect. 

When yours cuts out, does it die out around a specific RPM? Above it's out, below it runs?

Maybe it was my thread you came across regarding the splices in the harness.

And welcome to the forum.


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## saudade (Apr 10, 2010)

hoots007 said:


> .Sorry for jumping in...any help much appreciated...cheers


Welcome to the forum but this really should be in separate thread.


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## 4x4body (Nov 10, 2010)

unfortunately I do not have the parts to try out. I may have fixed my truck though. I removed the MAF to verify that the hotwire is still in good condition. Cleaned the MAF with the BG MAF cleaner from work, took battery cleaner and cleaned the terminals in the connectors for MAF, TPS, and Idle switch because they were green, and its been driving well ever since.
I'm afraid to drive it back to work without driving it around home some more first; work is 40 miles away. 
The symptom though is completely intermittent; it is not a specific rpm, specific temperature, load/no load; it just cuts out when it feels like it


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## saudade (Apr 10, 2010)

Corrosion in the connectors could certainly cause the problem. If you're confident you got it all out, go back and fill the connectors with dielectric grease (if you have't already). This will better protect them from further corrosion.

Keep us posted.


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## CMax03 (Jan 17, 2009)

Is the fuel pump a Z24i (fuel injection) fuel pump?


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## 4x4body (Nov 10, 2010)

The MAF cleaning definitely fixed it. I have driven it several hundred miles since. Now sadly it must sit in my driveway until January as there is no way it will pass emissions at this point; in January it will be an antique and exempt though!
Anyways I have also recently replaced my leaking heatercore to add heat back to the truck; and I've been painting this god awful smurf blue interior to black.
Also got a chance to take it off road for a minute, it had no problems with the mud hole; and climbed the inclines in 4low with ease.
Thanks for your inputs.


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