Fuel injection chip?

[cayox]

Hey guys i'm new to this website and I have a 1978 280Z (Automatic).

Anyways, I have a question. My Z is running very 'rich' the injectors are pushing to much fuel in, and the air to fuel mix is off so the black cloud its producing out of the exhaust is burnt gas. So when I press on the gas I get alot of smoke and not much acceleration. And sometimes it even stalls at stop signs and stop lights, its very embarrassing.

So I go to this classic Z repairer and he says it needs a $500 chip that will fix the problem.... Do any of you guys know if it will?? I didnt even know a '78 Z had a chip since its 29 years old

Have any of you guys ever had the same problem? And will this computer chip to my fuel injectors fix the problem.

Thanks, oh and I may be getting a black rubber air dam for under my bumper, are those cool?

Thanks

-Dylan

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[76Datsun280z]

Thanks, oh and I may be getting a black rubber air dam for under my bumper, are those cool?

Welcome to the site! I've got one on my 280z, and I think that it really dresses it up in the front. If you'd like, I can take a close up picture of it tomarrow if you want to see how it looks.

[TomoHawk]

Dude,

There's no "chip" on the ECU (Eletronic Control Unit.) It's just a dumb box, like a transistor radio, that takes inputs from sensors and opens the injectors as needed. As far as any of us can tell, there's no way to adjust it, even if it needed to be adjusted, or when installed at the factory.

The best thing you can do is to make sure all your connections are perfect with no corrosion, and the sensors are working properly. there are about 18 documents you need to get & read and do the job yourself.

Are you SURE that guy was an expert on the Datsun engines? from his repair suggestion, it sounds like he only knows modern fuel injection, of which I've heard many times, "Sure, we service fuel injected engines. We're experts at those."

There isn't anything with a microchip in it on a 280Z, unles you recently got a new radio system.

Welcome to the website.

thx

[cayox]

Welcome to the site! I've got one on my 280z, and I think that it really dresses it up in the front. If you'd like, I can take a close up picture of it tomorrow if you want to see how it looks.

Yeah man I would love to see it!

Tomohawk, thanks for the reply, and thats what he said, "It needs a new computer ship." maybe he said new "computer" I don't really remember, but im going to go by his word since he has been working on Z's for a long time... If it fix's it then I will be happy, and if it doesn't work.... Then Ill do it myself.

heres his site...

http://www.zspecialties.com/

Thanks guys

[76Datsun280z]

Alright, I'll get a picture tomarrow.

As Tomohawk said, there's no "chip". He must be talking about the ecu. Whatever Oliver said, I'm sure that he knows what he's talking about. Most his prices are over the top, so I'd probably see if I could find one cheaper else where.

[hls30.com]

Ther e are a couple of thngs to check as well.

1)Your cold start valve could be stuck in the or made to be in the "on" position.

2) A PO could have messed with the AFM, making it read more air in the system that there realy is

Both of those will richen the mixture as you have described, but could be in effect fooling your ecm.

Putting a 10K pot or a resistor on the temp sensor lead is an old trick user to richen the mixture by fooling the ecm into thinging the car was always running cold.

Bending the armature in the AFM can also be used to richen or lean out the mixture.

checking for these conditions is easy and could just give you a 10 minute small effort fix(by undoing them).

Will

Will

[Mr Camouflage]

$500? that must be parts and labour ($100 parts $400 labour)

If you feel like doing the labour yourself:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=170079858690

[TomoHawk]

You can get a good used ECU for a LOT less than 500. :mad:

So before you go buying a new one of those, you better make sure all your sensors (AFM, water temp, TPS, etc.), are working perfectly, and the connections are as "A-1" as you can get. Look for vacuum leaks, new fuel filter, air filter, etc., etc.,

Then get a new ECU. Otherwise, even a new one won't work. BTDT.

Don't forget to go read all the pertinent documentation, like the "280Z fuel injection book." That document itself could probably help you.

BTW, Are you driving your 280Z around WA in THIS weather???

[zbane]

Here's a link to the book TomoHawk mentioned.

http://www.atlanticz.ca/zclub/techtips/efisystem/280zfuelinjectionbook.pdf

It's in PDF, so it may take a little bit to load, but it's definately worth saving to file.

Before you go over to Oliver, try to figure it out for yourself. You'll be saving yourself some money ($500!), and you'll be learning about your car.

[hls30.com]

If you really think an ECM will solve your problem, I have quite the collection I was getting ready to ebay, pm me the numbers off yours, and I'll send you a replacement for $30 including shipping if it is in my collections.

[rewiredz]

isnt there an adjustment on the AFM that can lean out or richen the amount of gas. i know that there is a plug that i can take out of mine and there is a screw that adjusts the mixture.

Doc1.doc

[TomoHawk]

Changing the tension of the spring will affect the signal the AFM sends to the ECU. The plug covers an air bypass screw, but there's no documention about what it's for or how to adjust it. IMO, it allows some air to get behind the flap, so it doesn't deflect as much, or dampens any oscillating.