90 240 what to do? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

TPnTX · 01-11-2002, 08:34 AM

Some problem solving needed. 90 240. I was sucking up the gas. I just bought so I thought I'd tune it up a bit. Plugs, plug wires, rotor, rotor cap, all filters, o2 sensor. That certainly didn't hurt things any but barely noticed MPG inprovement. Then.....

I notice the fuel injector elec. connectors where cracked.  At first I was going to just check them and maybe seal with silicon or something. I wiggle the #2 connector while the car was running and the motor started sputting and shaking. I wasn't able to get it to stop doing this so I popped the pin out and tool the connector off. I saw then how corroded it was both on the wire and the injector. So I cleaned it. Wire brush, file, elect spray. That didn't help. So I went and bought new connector harness from Nissan. They didn't sell one for the 240 but the 300zx would work IF you cut and spliced the wires which I did. I replaced all of them cleaning each pair of connectors on the injectors. It still ain't fixed.
It idles fine. It shackes and sputters on initial/slow acceleration.  If you get on it it runs smooth. Revs up real good too. Driving on the highway, if you accelerate , it runs great but when you settle at a speed and the r's are low it sputters some.

I don't know, it didn't do this before I started jacking with the connectors.

I was also suprised at how easy you can rotate the injector. You like clockwise and couter clockwise.

I'll continue to track this down and hopefully find a solution, but if anyone has seen this before I'd sure appreciate some pointers.
Right now because of the highway sputter I'm really using some gas. My 92 V6 Chevy pickup gets better MPG.

bing · 01-11-2002, 09:03 AM

im sorry i dont have a solution for you, but i have a 90 s13 as well and i get the worst mpg in history, i did all that tune up stuff when i got it and just did a full synthetic oil change and stillnot seeing a difference, plus i only use 93 octane gas from the same place every time, still no improvment...

if any one has a good solution im all ears... or eyes as it were

roycenagger · 01-11-2002, 10:07 AM

Sounds like you need new injectors.  Also it would be good to replace all of your vacuum hoses and rubber fuel lines.  They are really old now if they haven't been replaced before.  Clean or replace your air filter and fuel filter.  If your injector connectors were corroded then all the other engine bay harness connectors are probably corroded too.  Clean them up as well.
Remove the intake runner connecting to your throttle body and clean the throttle body butterfly with carburator cleaner (open it up and clean inside as well as you can too).  It's probably really gummed up.
After doing this and after running it for a while, reset the ECU (pull fuse or disconnect battery for 20-30 min.).

My 2 cents.

-Royce

*sykikchimp* · 01-11-2002, 10:32 AM

Don't forget Fuel Filter.

I've seen a lot of instances where a dirty clogged fuel filter is the cause of your situation

TPnTX · 01-11-2002, 10:36 AM

Yeah thanks guys but I listed the filters in the "done" list.

*sykikchimp* · 01-11-2002, 11:26 AM

doh..  sorry..  "all filters".. registered as "air filter" in my brain for some reason..

*sykikchimp* · 01-11-2002, 11:30 AM

also just thought of this too..

try getting some Carb cleaner and cleaning the MAF.  this sometimes does wonders as well.

T240dankman · 01-11-2002, 11:36 AM

TP-  I've got a '90 too and it's funny because I have the same problem.  I had miss, and couldn't figure out what it was, I finally pinned it down to the injector pigtails and injectors being corroded at the connection.  The corrosion is like a green color and you probably want to check all other electrical components like your relays and any other electrical plugs for similar corrosion under the hood.  But I did the same thing trying to wire brush that crap out, and after i did my miss didn't completely go away but it changed.  So your best bet if you already replaced the pigtail would be injectors but unfortunately good aftermarket injector will probably cost you $100 a piece.  Good luck Man.

TPnTX · 01-11-2002, 12:33 PM

T240, so is that what you ended up doing, replace the injectors?

I just went out and lunch and messed with the connectors. I used to be able to wiggle them and cause it to happen at any idle. Now I can't seem to make one misfire at a regular idle but with the e-brake on, in gear, I throttle it up some and there it is. So it's a load on the motor. Ahhh. I tell ya every thing fits real well and like I said I've even taken a file to the injector pins. I saw that green corrosion you talked about and I thought I got it all off.

That would suck to have to replace injectors because of a connection issue as opposed to failing, uh functionality. That corrosion must have been holding them together until like a dummy I had to go fix something that wasn't even broke.

yenpit · 01-11-2002, 01:03 PM

injector rubber seals..?? these too will dry rot and break down creating a vac leak. when u wiggled the injector u may have "broken" the seal of crud and gum that builds up...thus creating a vac leak. could be a cheap fix b4 buying injectors like roycenagger said, but they too could be bad.

roycenagger · 01-11-2002, 01:05 PM

My original injectors lasted 7yrs before the common leaking issue raised it's ugly head.  Made the mistake of replacing them w/rebuilts.  They only lasted 3yrs before going out, one at a time.  On the rebuilts, right when they started giving out, I could twist on the connectors, as you have been doing and the car would start missing.   I have since replace them all w/factory ones (got a discount at Courtesy Nissan) for about $100 a piece.  I think Nissan has resolved the original leaking issues and so I think it's good to go for at least the next 8 yrs.  (1990 fastback)

-Royce

TPnTX · 01-14-2002, 07:29 AM

Okay I think I'm going to try the seal replacement. I've never pulled injectors before but doesn't  LOOK too complicated. I've searched here and didn't find many details on doing this. So If anyone has any "watch out for..." advice, I'd appreciate it.

Should you even be able to twist or turn the injectors at all or does a correct seal make it at least hard to twist. These now twist with little resistance.
If I can ever get this thing running good I'll be on the body work. It's pretty straight and interior is excellent. The problem is the paint. "Sea Foam" green. Who the #### would want a Sea Foam green sport car?

01-11-2002, 08:34 AM	#1
TPnTX Join Date: Jan 2002 Posts: 41 Trader Rating: (0) Feedback Score: 0 reviews	Some problem solving needed. 90 240. I was sucking up the gas. I just bought so I thought I'd tune it up a bit. Plugs, plug wires, rotor, rotor cap, all filters, o2 sensor. That certainly didn't hurt things any but barely noticed MPG inprovement. Then..... I notice the fuel injector elec. connectors where cracked.  At first I was going to just check them and maybe seal with silicon or something. I wiggle the #2 connector while the car was running and the motor started sputting and shaking. I wasn't able to get it to stop doing this so I popped the pin out and tool the connector off. I saw then how corroded it was both on the wire and the injector. So I cleaned it. Wire brush, file, elect spray. That didn't help. So I went and bought new connector harness from Nissan. They didn't sell one for the 240 but the 300zx would work IF you cut and spliced the wires which I did. I replaced all of them cleaning each pair of connectors on the injectors. It still ain't fixed. It idles fine. It shackes and sputters on initial/slow acceleration.  If you get on it it runs smooth. Revs up real good too. Driving on the highway, if you accelerate , it runs great but when you settle at a speed and the r's are low it sputters some. I don't know, it didn't do this before I started jacking with the connectors. I was also suprised at how easy you can rotate the injector. You like clockwise and couter clockwise. I'll continue to track this down and hopefully find a solution, but if anyone has seen this before I'd sure appreciate some pointers. Right now because of the highway sputter I'm really using some gas. My 92 V6 Chevy pickup gets better MPG.

01-11-2002, 09:03 AM	#2
bing Post Whore! Join Date: Oct 2001 Location: ontario canada Posts: 2,699 Trader Rating: (21) Feedback Score: 21 reviews	im sorry i dont have a solution for you, but i have a 90 s13 as well and i get the worst mpg in history, i did all that tune up stuff when i got it and just did a full synthetic oil change and stillnot seeing a difference, plus i only use 93 octane gas from the same place every time, still no improvment... if any one has a good solution im all ears... or eyes as it were

01-11-2002, 10:07 AM	#3
roycenagger Join Date: Dec 2001 Posts: 12 Trader Rating: (0) Feedback Score: 0 reviews	Sounds like you need new injectors.  Also it would be good to replace all of your vacuum hoses and rubber fuel lines.  They are really old now if they haven't been replaced before.  Clean or replace your air filter and fuel filter.  If your injector connectors were corroded then all the other engine bay harness connectors are probably corroded too.  Clean them up as well. Remove the intake runner connecting to your throttle body and clean the throttle body butterfly with carburator cleaner (open it up and clean inside as well as you can too).  It's probably really gummed up. After doing this and after running it for a while, reset the ECU (pull fuse or disconnect battery for 20-30 min.). My 2 cents. -Royce

01-11-2002, 10:32 AM	#4
sykikchimp WOW addicted Join Date: Dec 2001 Location: the moon Age: 44 Posts: 6,525 Trader Rating: (0) Feedback Score: 0 reviews	Don't forget Fuel Filter. I've seen a lot of instances where a dirty clogged fuel filter is the cause of your situation

01-11-2002, 10:36 AM	#5
TPnTX Join Date: Jan 2002 Posts: 41 Trader Rating: (0) Feedback Score: 0 reviews	Yeah thanks guys but I listed the filters in the "done" list.

01-11-2002, 11:26 AM	#6
sykikchimp WOW addicted Join Date: Dec 2001 Location: the moon Age: 44 Posts: 6,525 Trader Rating: (0) Feedback Score: 0 reviews	doh..  sorry..  "all filters".. registered as "air filter" in my brain for some reason..

01-11-2002, 11:30 AM	#7
sykikchimp WOW addicted Join Date: Dec 2001 Location: the moon Age: 44 Posts: 6,525 Trader Rating: (0) Feedback Score: 0 reviews	also just thought of this too.. try getting some Carb cleaner and cleaning the MAF.  this sometimes does wonders as well.

01-11-2002, 11:36 AM	#8
T240dankman Join Date: Jan 2002 Posts: 4 Trader Rating: (0) Feedback Score: 0 reviews	TP-  I've got a '90 too and it's funny because I have the same problem.  I had miss, and couldn't figure out what it was, I finally pinned it down to the injector pigtails and injectors being corroded at the connection.  The corrosion is like a green color and you probably want to check all other electrical components like your relays and any other electrical plugs for similar corrosion under the hood.  But I did the same thing trying to wire brush that crap out, and after i did my miss didn't completely go away but it changed.  So your best bet if you already replaced the pigtail would be injectors but unfortunately good aftermarket injector will probably cost you $100 a piece.  Good luck Man.

01-11-2002, 12:33 PM	#9
TPnTX Join Date: Jan 2002 Posts: 41 Trader Rating: (0) Feedback Score: 0 reviews	T240, so is that what you ended up doing, replace the injectors? I just went out and lunch and messed with the connectors. I used to be able to wiggle them and cause it to happen at any idle. Now I can't seem to make one misfire at a regular idle but with the e-brake on, in gear, I throttle it up some and there it is. So it's a load on the motor. Ahhh. I tell ya every thing fits real well and like I said I've even taken a file to the injector pins. I saw that green corrosion you talked about and I thought I got it all off. That would suck to have to replace injectors because of a connection issue as opposed to failing, uh functionality. That corrosion must have been holding them together until like a dummy I had to go fix something that wasn't even broke.

01-11-2002, 01:03 PM	#10
yenpit Zilvia Addict Join Date: Sep 2001 Location: Holland Michigan Posts: 798 Trader Rating: (0) Feedback Score: 0 reviews	injector rubber seals..?? these too will dry rot and break down creating a vac leak. when u wiggled the injector u may have "broken" the seal of crud and gum that builds up...thus creating a vac leak. could be a cheap fix b4 buying injectors like roycenagger said, but they too could be bad.

01-11-2002, 01:05 PM	#11
roycenagger Join Date: Dec 2001 Posts: 12 Trader Rating: (0) Feedback Score: 0 reviews	My original injectors lasted 7yrs before the common leaking issue raised it's ugly head.  Made the mistake of replacing them w/rebuilts.  They only lasted 3yrs before going out, one at a time.  On the rebuilts, right when they started giving out, I could twist on the connectors, as you have been doing and the car would start missing.   I have since replace them all w/factory ones (got a discount at Courtesy Nissan) for about $100 a piece.  I think Nissan has resolved the original leaking issues and so I think it's good to go for at least the next 8 yrs.  (1990 fastback) -Royce

01-14-2002, 07:29 AM	#12
TPnTX Join Date: Jan 2002 Posts: 41 Trader Rating: (0) Feedback Score: 0 reviews	Okay I think I'm going to try the seal replacement. I've never pulled injectors before but doesn't  LOOK too complicated. I've searched here and didn't find many details on doing this. So If anyone has any "watch out for..." advice, I'd appreciate it. Should you even be able to twist or turn the injectors at all or does a correct seal make it at least hard to twist. These now twist with little resistance. If I can ever get this thing running good I'll be on the body work. It's pretty straight and interior is excellent. The problem is the paint. "Sea Foam" green. Who the #### would want a Sea Foam green sport car?