1978 280Z Fuel Pouring From Throttle Body

[Irish Wake]

Grant thanks I tried to download the service manual but it won't work on my Ipad

[grantf]

Hmm, Ipads cannot read pdf files? I could email you the efi chapter in pdf. Or try a P.C. I have the 77 Manual, but I reference the 78 more often because it is laid out in separate files per chapter.

I have the Hains and Chilton manuals but they are next to useless compared to the FSM, so I never even open them anymore.

Edited July 30, 2012 by grantf

[Wade Nelson]

It could be ANY injector that's stuck open, although the CSV is the most likely culprit.

[Irish Wake]

Update I left the key on yesterday when I went to the auto parts store and when I returned and discovered my bone head move I found the motor hydro locked with fuel and a ton of fuel in the oil.

I changed the oil and plugs and found that the engine ran better when I disconnected the 6th injector. So I picked up 6 injectors from Autozone and am in the process of changing them out.

I also found a rip in the boot between the AFM and the throttle body so I got two boots coming from MSA along with a cold start valve and a thermo time switch. I like to keep everything stock and everything working as originally designed.

I hope all this will solve my problem!

Thanks

Randy

Edited July 31, 2012 by Irish Wake
Misspelled words

[Irish Wake]

Grant if you can email me the file it would be great send it to premiergrowers@bellsouth.net

[Zed Head]

Somehow Wade must have cursed you when he mentioned that any injector could be open. Amazing.

The more symptoms you describe though, the more it becomes apparent that reading the Engine Fuel section of the FSM would really help you out.

There are a few things wrong with what just happened. First, the fuel pump should not have power when the key is on unless the engine is running. You couldn't fill your crankcase with gas unless the fuel pump was running. So that's not right. Kind of missed that in Post 1. And, unless the injector is physically jammed open, the only way to get constant fuel flow is if it's constantly grounded since the injectors always have power when the key is on. So your problem might just be a shorted wire on the ground side of the injector circuit. Or it could be a shorted ECU, which happens sometimes.

You should get that FSM chapter and a multimeter and do some testing before you install the injectors, you might be wasting time and money. Or, at least, turn the key on with all of the injectors attached to see if they're all stuck or just one, before you install all new injectors.

In the beginning, it looked a like a simple problem with a simple solution but now it's looking more complicated. It might be time to get methodical.

The FSMs are in ZIP form on the xenons30 site, maybe that's why you couldn't open them. You have to download then unzip them.

[grantf]

I have sent you the Fuel section of the FSM and the EFI bible, I hope you can open them and they help. You really need the whole FSM for you car though, including an understanding of the wiring that is involved with the EFI system. This helps greatly in diagnosing these problems. I agree with zead head 100%

As a mater of fact He was one of the people that helped me track down some of my troubles in the past regarding the fuel injection system.

You need to read through and understand how it works a little then do some simple tests. then you will find the culprit. It's not that difficult once you understand the basics.

I did not mean to confuse the situation but I had the conectors swapped on mine in the past. It's an easy mistake to make and resulted in a similar condition.

[grantf]

Again let us know if you got the files. You should do a continuity check at the ECU connector to be shure that the WTS is operating normally.

[Irish Wake]

Thanks Grant I got them

[Irish Wake]

Zed I'm lost and confused now. Everything I described happened. Sat night my son called and said the car would start up and immediately die I went to the car Sunday and the air filter housing was full of gas and when I pulled the boot from the throttle body gas poured out in a stream.

It may be that all the fuel in the engine happened on Sat but I got it cranked and drove it home and when I returned from the parts store, the engine wouldn't turn over and when I removed the spark plugs and cranked it fuel shot out of each cylinder about 10 feet in the air like a fountain.

When I plugged the line and disconnected the CSV the fuel leak from the throttle body stopped. When I turned the key to the start position I could hear the fuel pump on and turn off when I turned the key off.

I'm in the position of having little time so I am trying to replace any parts that could cause the problems so the car will be reliable for my son when he leaves for college.

Could the car being parked nose down cause the fuel to siphon into the engine if the pressure regulator was bad? Just grasping at straws I guess

Thanks

Randy

[MotoManMike]

parking nose down wouldn't cause it to flood. I had a vehicle do this years ago and it was the injector seals, like a $5.00 part, might not be your issue but its what i'm guessing is the issue. It could be that cold start valve, I wouldn't think a bad regulator would let it blow through the injectors that bad. WORD TO THE WISE, CHANGE YOUR OIL MULTIPLE MULTIPLE TIMES AFTER REPAIR!!!! Gas will wash bearings out faster than you can shut that thing off if it runs like this. Don't be surprised if oil leaks pop up after this either, sometimes a motor filled with gas will then leak from the oil pan, rear and front main seals because the gas makes the rubber seals swell. Been there, not fun but at least you know what to look for after its fixed.

Edited July 31, 2012 by MotoManMike
forgot a word

[Zed Head]

Over here on the other side of the internet we have to make assumptions about how all of the other parts on your engine are working, so it's easy to miss a critical clue. That's why the methodical approach, with the FSM and a meter, works best, starting from scratch.

I still see something that doesn't sound right. You said that you can hear the pump when you turn the key to start. "Start" is when the engine is cranking, so unless you disconnected the small wire at the starter, you wouldn't be able to hear the pump because of the noise from the starter turning the engine. Maybe you mean "Run" or "On" which is the position the key is in right before Start. The pump should not run unless the starter is cranking, or the the engine is running. Maybe you have a relay that's shorted, causing the fuel pump to run even with the key off? Or did you leave the key On when you went in to the store?

You never said if the CSV that you took off had constant power causing it to stay open or if it was stuck physically. That would be an important clue. Something weird happened to cause several problems at the same time. CSV stuck, pump running, injectors open... I would break out a multimeter and take some measurements.

How much time do you have left?