Update on my SE (with Questions)
03-13-04, 07:09 PM
#1
EliteHardcoreCannuckSquad
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Join Date: May 2001
Location: Acton, Ontario, Canada
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Update on my SE (with Questions)
Okay, so some of you may have been following along with my -SE problems:
https://www.rx7club.com/showthread.p...hreadid=280257
https://www.rx7club.com/showthread.p...hreadid=280024
https://www.rx7club.com/showthread.p...hreadid=279791
But now I'm in the proccess of replacing the injectors and vacum hoses, as well as cleaning the intake and adding a grounding kit.
I've discovered a couple things.
1.) While removing the fuel rail I noticed a rattle from under the plastic cap covering the pulsation damper. I poped off the cap, and discovered the little screw in there just rolling around lose.
a.)What does it do? Could it be related to my problems?
b.)How tight should it be screwed in?
2.) While dissasembling the intake, I noticed the secondary passages in the manfold are caked on with a nasty oily carbon crust. It starts on the backside of the butterflies and goes all the way down the lower manifold.
a.)What is it and how did it get there?
b.)How do I make sure it doesn't come back?
Thanks!
-Spencer
https://www.rx7club.com/showthread.p...hreadid=280257
https://www.rx7club.com/showthread.p...hreadid=280024
https://www.rx7club.com/showthread.p...hreadid=279791
But now I'm in the proccess of replacing the injectors and vacum hoses, as well as cleaning the intake and adding a grounding kit.
I've discovered a couple things.
1.) While removing the fuel rail I noticed a rattle from under the plastic cap covering the pulsation damper. I poped off the cap, and discovered the little screw in there just rolling around lose.
a.)What does it do? Could it be related to my problems?
b.)How tight should it be screwed in?
2.) While dissasembling the intake, I noticed the secondary passages in the manfold are caked on with a nasty oily carbon crust. It starts on the backside of the butterflies and goes all the way down the lower manifold.
a.)What is it and how did it get there?
b.)How do I make sure it doesn't come back?
Thanks!
-Spencer
Last edited by smnc; 03-13-04 at 07:14 PM.
03-13-04, 07:21 PM
#2
If the screw fell out of the PD, you may be leaking fuel. You need to fix it to prevent a fire. I don't know if that would cause your problem though. There is a thread on here that discusses using a banjo bolt in place of the PD with no appent ill effects (may be harder on the pump and injectors though).
Kent
Kent
03-13-04, 08:02 PM
#3
EliteHardcoreCannuckSquad
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Join Date: May 2001
Location: Acton, Ontario, Canada
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It's screwed back in, loosely for now. I don't want to tighten it until I know how far to go...
I don't think I was leaking any fuel... although my gas mileage was getting really brutal before the car stoped working...
I don't think I was leaking any fuel... although my gas mileage was getting really brutal before the car stoped working...
03-13-04, 10:02 PM
#4
Tennis, anyone
mmmmmmmmm.... let me tell you how my car started to act, okay. was running fine, real good really.got home one night parked the car,, the next day get in and try to start it,,,,nothing.. leave the car alone for a couple of days,,,,,nothing, kill the battery trying to start it. charged the battery overnight,, try it,,,nothing.. the first thing i pull is the main fuel hose at the delivery pipe and put a guage in-line,turn the key 'on' and push open the MAS flapper door, the fuel pump works, but real low fuel presure. buy a new fuel pump. before installing it i used the compresser and blew air through the main fuel hose and the return line. Installed the new pump,,samething
way low fuel presure.okay,,,i know from the pump to the firewall is clear,,so it's either end of the car, so i drop the gas tank, remove the plate/pickups blow those out.everything else looks okay. install the tank, get gas and the thing starts, smokes like a bitch, runs rough, still low fuel presure , but enough to run. So now i'm thinking it's got to be from the firewall forward, pull the entire EFI to get to the delivery pipe/injectors check the connections, pull the injectors, blow air through both of them,buy new grommets/o-rings install the injectors. tighten the bolts that hold down the fuelrail, now theres better fuel presure, i can hear fuel passing through the return line, reinstall all the EFI stuff, check all vacum hoses, and the car starts,,smokes like a bitch and runs rough,,,still. the smoke goes away, the engine spins up but misses,,, bought new plugs,,samething still,, and that is where i'm at right now...... ?????????? injectors???????? or CPU????????? there are so many 'valves' that could go out that pisses me off. never touched the timing, didn't turn anything on the EGI. i haven't replaced any vacum hoses though either.
were in the same ******* boat,,,buddy
way low fuel presure.okay,,,i know from the pump to the firewall is clear,,so it's either end of the car, so i drop the gas tank, remove the plate/pickups blow those out.everything else looks okay. install the tank, get gas and the thing starts, smokes like a bitch, runs rough, still low fuel presure , but enough to run. So now i'm thinking it's got to be from the firewall forward, pull the entire EFI to get to the delivery pipe/injectors check the connections, pull the injectors, blow air through both of them,buy new grommets/o-rings install the injectors. tighten the bolts that hold down the fuelrail, now theres better fuel presure, i can hear fuel passing through the return line, reinstall all the EFI stuff, check all vacum hoses, and the car starts,,smokes like a bitch and runs rough,,,still. the smoke goes away, the engine spins up but misses,,, bought new plugs,,samething still,, and that is where i'm at right now...... ?????????? injectors???????? or CPU????????? there are so many 'valves' that could go out that pisses me off. never touched the timing, didn't turn anything on the EGI. i haven't replaced any vacum hoses though either.
were in the same ******* boat,,,buddy
03-13-04, 10:26 PM
#5
84SE-EGI helpy-helperton
SMNC - on your questions, I have done the '6'-port cleanout job, and can offer the following advice on your 2 questions;
1) the fuel Pulsation Dampner on the fuel rail is one of a pair of dampners that help to keep hydraulic vibrations out of the fuel system - these vibrations in the high pressure fuel line can lead to 'water-hammer' effect on your injectors, gradually beating them to death. If the pulsation dampner isn't leaking - it's working. The small screw in the front is used to control the amount of pressure applied to the metal dampening 'diaphragm', and should be snug, but not tight. The other end of your fuel system has the other PD, and it's mounted to the fuel pump. Again, if it's not leaking fuel actively, it's not a problem - these don't go out frequently in early model cars - in later model 7's, it does, but not SE's with any regularity (lower fuel pressure than later cars).
2) The black carbon deposits that you see in your intake system for the secondaries is pretty common - my 170k mile SE had carbon just like yours in BOTH primary and secondary channels all the way from the TB to the Dynamic Chamber and through the plenums. Had it clean it out with carb cleaner and a toothbrush. If you've never cleaned yours out, with similar mileage, yours will look the same. The fact that you only see it on your secondary side could be that you don't get on it very often, opening up the secondaries and '6'-ports. Gradual backflow of air/fuel mix through the rotors and secondary plenum would lead to this buildup over time. Remember, there are no injectors in the secondary plenum, only the center housing, so the air/fuel mix is going through the rotor space on intake cycle and backing up the secondary side... Very likely, your '6'-ports are going to be black and cruddy just like your secondary plenum. A good cleaning should get this back into working order.
Added on edit: Something else I noticed is that if your OMP injectors on the primary side weren't working, this could be a reason why you don't have any 'crust' on the primary plenums... Definitely check that to make sure you're getting oil flow through the OMP regulators and that it's hooked up to a vacuum source at the Dynamic chamber and rat's nest.
What you see right now is very close to doing a full '6'-port cleaning anyway, so think about it. For the cost of a few more gaskets (lower intake manifold to engine), and you could clean it all out and be back on the road with more power and throttle response.
MarkPerez - I'd be happy to help you troubleshoot your issue in another thread, and don't want to jack the original here. Sounds like you may be dealing with a bad fuel filter, but light up another thread and let's talk about it.
HTH, guys.
1) the fuel Pulsation Dampner on the fuel rail is one of a pair of dampners that help to keep hydraulic vibrations out of the fuel system - these vibrations in the high pressure fuel line can lead to 'water-hammer' effect on your injectors, gradually beating them to death. If the pulsation dampner isn't leaking - it's working. The small screw in the front is used to control the amount of pressure applied to the metal dampening 'diaphragm', and should be snug, but not tight. The other end of your fuel system has the other PD, and it's mounted to the fuel pump. Again, if it's not leaking fuel actively, it's not a problem - these don't go out frequently in early model cars - in later model 7's, it does, but not SE's with any regularity (lower fuel pressure than later cars).
2) The black carbon deposits that you see in your intake system for the secondaries is pretty common - my 170k mile SE had carbon just like yours in BOTH primary and secondary channels all the way from the TB to the Dynamic Chamber and through the plenums. Had it clean it out with carb cleaner and a toothbrush. If you've never cleaned yours out, with similar mileage, yours will look the same. The fact that you only see it on your secondary side could be that you don't get on it very often, opening up the secondaries and '6'-ports. Gradual backflow of air/fuel mix through the rotors and secondary plenum would lead to this buildup over time. Remember, there are no injectors in the secondary plenum, only the center housing, so the air/fuel mix is going through the rotor space on intake cycle and backing up the secondary side... Very likely, your '6'-ports are going to be black and cruddy just like your secondary plenum. A good cleaning should get this back into working order.
Added on edit: Something else I noticed is that if your OMP injectors on the primary side weren't working, this could be a reason why you don't have any 'crust' on the primary plenums... Definitely check that to make sure you're getting oil flow through the OMP regulators and that it's hooked up to a vacuum source at the Dynamic chamber and rat's nest.
What you see right now is very close to doing a full '6'-port cleaning anyway, so think about it. For the cost of a few more gaskets (lower intake manifold to engine), and you could clean it all out and be back on the road with more power and throttle response.
MarkPerez - I'd be happy to help you troubleshoot your issue in another thread, and don't want to jack the original here. Sounds like you may be dealing with a bad fuel filter, but light up another thread and let's talk about it.
HTH, guys.
Last edited by LongDuck; 03-13-04 at 10:28 PM.
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