92fairladyz

My Z still won't start. It's been 6 days now. We know we have air and spark. We also know the reason I'm not starting is because I am not receiving fuel to the cylinders. I just can't figure out why for the life of me. I am so close to junking my Z and giving up. Somebody please help. I have some questions I need answered.
1) If I turned my CAS and heard all 6 injectors click, wouldn't that count out a faulty signal,faulty CAS, faulty injector connectors, or a faulty PTU?

2) What are soem reasons fuel doesn't go into the cylinders when everything else seems fine?

I still need to test my fuel pressure. I just don't have a guage yet. I just replaced my fuel pressure regulator hoping that would do something but it didn't. I just wasted my money.

We disconnected the battery for about 2 days while the auto hobby shop was closed. We went back and reconnected it and the car sounded like it wanted to turn a little more than it has been but that only lasted for half a second before it went back to the normal sound of "trying" to turn.

<b>Things verified:</b>
1) Injectors click when turning CAS
2) Battery charged and even used a jumper
3) Fuel lines all correctly connected. None reversed.
4) Fuel goes in supply and comes out return line.
5) All vacuum hoses connected
6) No vacuum leaks
7) New Fuel Pressure Regulator installed
8) Fuel pump turns on with key
9) Over half a tank of gas
10) We have air flow
11) Coil pack connectors click
12) Spark plugs spark when grounded
13) Grounds on rear of plenum are connected (3 total)
14) All connectors are connected
15) Corrosion cleaned off connectors
16) Car started when carb & choke cleaner was sprayed into throttle bodies

Somebody please help before I give up.

silvrhand

My guess is fuel, you need a fuel pressure gauge and see if you are getting pressure up near the fuel filter. You did take off your fuel filter and see if you can blow through it right?

CanyonCarver

As silvrhand stated the next thing that has to be done is check the fuel pressure.

Coupla thoughts....... the egr valve and tubes are all hooked back up or blocked off? When you pull the plugs after trying to start it, are they wet or dry? Have you vacuum checked the fuel damper?

When trying to start it, have you tried holding the throttle wide open? or pumped it open and closed?

92fairladyz

We know the fuel filter is flowing because fuel goes from supply to return. Fuel also spills from the filter. I'm going to do the pressure test though. I need to get a fuel pressure guage.

As for the EGR tubes, they are all hooked back up. They had all sorts of crud in them (really caked in there) but we cleaned it all out. We added new gaskets to them as well. We pulled the plugs to do the spark test and they were dry. They were pretty browned out but they were still sparking just fine. How do I vacuum check the damper? We removed the vacuum line and plugged it while trying to start the car. Is that the same thing?

We tried the throttle both ways. I've pumped it and I've also tried holding it wide open.

bradyg

does it even fire at all and have you checked for compression

92fairladyz

It will just try to turn over but will not fire. It only fired once and that was when we sprayed carb cleaner into the throttle bodies but that only lasted for a second even with the gas applied.

I have not done a compression test.

bradyg

what did the car run like before it stoped starting like did anything weird happen when and then it just died and wouldnt start

bardabe

check your temperature sensors, and Oil pressure sensors. My friend had the same problem with his RB25 since the sensor was damaged the ECU thought engine way sayyy to hot to be running. so the ECU won't give you spark. yuo can also try reseting the ECU, changing Oil PSure sensor, and temperature sensor. maby your injectors are cloged. get a little LED light and make sure the INjectors are getting power. simply conect the LED to the injector plug. if it dosent light up. no power, if it lights up and injectors don't spit out fuel then they are cloged.

CanyonCarver

You can generally vacuum check anything by sucking on the vacuum line with your mouth. If you can pull air thru, it's bad or has a leak.

I asked about the wet or dry plugs because it's easy to be fooled by thinking there's no fuel when the plugs are actually fuel fouled. sometimes you can't see that they're fouled because the wet fuel is up inside between the insulator and the metal casing causing it to short out.

I have stated in the past that in approx 50% of my diagnosis experience, if you think it's a fuel problem it ends up being air or spark and vice-versa.

In checking your fuel pressure, you don't need a "T" or fitting. All you need is a gage that you can hose clamp into the end of the fuel line. If you check it this way, the pressure that you will see will be the max pump pressure of 80 psi or so. If the pressure doesn't come up, you might try bypassing the fuel pump controller by running battery power straight to the fuel pump connector.

Riz Z Speed

have you checked the fuel pump itself?
Last time i checked no fuel to the engine is usually casued by a bad pump. Are you certain that the pump works? If I remember correctly, the TT pump has two operating stages, a low and high output. The low output may not be functioning properly which would cause the fuel to stop flowing to the engine.

snwbrderphat540

this happened to my friends 73 'cuda. we accidently ran the tank empty and filled it up and almost barley got it to run then just take a crap. then nothing after a bit. we thought it had perhaps flogged the fuel filter with sediment in the tank it finally sucked down. or a bad fuel pump. it was both, we had to re run all new fuel lines becuase there was some sort of silicon stuck inside them and the fuel pump went to. after that though its been puring like a kittin. see it gave fuel but not enough to run. so id look towards ur pump or possibly unknown crap in the lines. probly fuel pump though.

92fairladyz

Fuel pump is fine. We tested it today. I have pressure in the lines and the pump works properly when the key is turned on and off. I also just replaced both my FPR as well as my fuel damper. Fuel just isn't being fired through the injectors. It is either a mechanical issue (very unlikely that all 6 injectors went bad or were clogged while the lines are good) or it's electrical (signal that tells injectors to spit isn't getting to any of the injectors even though turning the CAS causes them all to click).

92fairladyz

I'm going to be re-pulling my plenum on Wednesday. This is where I stand as of now:
1) Fuel flows fine through entire system
2) Pressure is good
3) Fuel flows through injector screens but does not spit out the injectors
4) Turning the CAS causes the injector solenoids to open and close which means the metering pin is opening and closing but still no fuel is spitting out
5) Apparently turning the CAS and hearing the clicks has proven my circuit is complete so any electrical problem suspicions have effectively been eliminated.

I'm going to inspect my injectors and see if there is any way to clean them. If they are clogged, it has to be at the metering pin. Maybe some sediments have settled into that area on all 6 injectors.

CanyonCarver

When you pull the plenum again, you can 100% verify that the injectors are working by pulling the whole fuel rail, plugging the injector connectors back in, and then testing them by turning the CAS like you did before when they were installed. Only doing it this way, you should see the injectors spraying fuel.

silvrhand

If one injector was dead also it would fire, I would think you are looking too deep at this point, it's got to be something the affects the *entire* system, such as fuel/spark at this point.

maybe the ECU is dead, I'm sure at this point but you have thrown it into diag mode to check for codes right?

92fairladyz

I've run the ECU diagnostic. At first I was getting a Code 34 but then I realized I had the VTC connector and the detonation sensor connector swapped. I swapped them back and ran codes again and got the 55. ECU is working okay. Since my CAS clicked the solenoids on the injectors, my electrical system is okay. I have visually verified spark on my plugs. I guess I'll pull the fuel rail and check for fuel spray when the injectors click by turning the CAS. I should be able to do that on Wedesday.

CanyonCarver

I'm thinking the injectors will be fine. I'm also thinking it's a major air leak that you'll hopefully find when you remove the plenum. Remember fuel, air and spark. Through all of your posts, you have verified fuel and spark.

Did you see my other post about verifying that the egr valve is correctly hooked up to the egr solenoid? If it's incorrect and the egr valve is getting vacuum when you try to start the motor, there'll be enough of an air leak to keep it from starting.

Good luck.

92fairladyz

Do you have any pics of the way the hoses connect to the EGR valve & solenoid? Remember, I bypassed the throttle bodies. I'm almost positive they are all hooked up right.

I was thinking the air was fine since it did start with carb cleaner in the throttle bodies but somebody mentioned the A/F ratio might've been just right to start but then die again since I added the carb cleaner.

CanyonCarver

Yes, with a big air leak, adding carb cleaner will richen the AFR enough to allow it to start.

Here is the EGR Diagnostics ---->>>> EGR Diag.

Picture "B" shows the solenoid plumbing.

92fairladyz

Well, after 13 days I finally got my Z up and running again. We pulled the plenum for the 2nd time today. We removed the fuel rail to verify the injectors were not spitting. We wanted to see it with our own eyes. Well, we got it out and saw #1 was spitting just fine when we turned the CAS. We weren't getting anything out of #2-#6. We took the #1 connector and plugged it into #3 and it spit fine. When we put it on #2, we got nothing. We decided to put the connector on backwards just for the heck of it and it decided to spit. Each injector connector has a groove in it so it can only go on one way. We forced #2-#6 to go on backwards and all of a sudden they all started spitting when I turned the CAS. For some reason #2-#6 is wired funny but #1 has to go on correctly. I guess when my friend was listening to the injectors click while I turned the CAS (with the plenum on), he apparently was only hearing #1 click but thought it was all the others too. That's why we removed the fuel rail. We wanted to visually verify. I was even able to reuse the old plenum intake gasket since no heat had been applied to it yet. It was still in great shape. Now I'm up and running better than ever. I even fixed my oil leak at my valve cover gaskets so it wasn't all in vain. Thanx for all the help guys.

japanz

Congratulations on the repair and it is a good note for anyone in the future doing a similar job.