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Update.
I am about to make an appointment at the mazda service shop in order to remove the UIM and check for vacuum leaks.
When I removed the BAC valve I noticed that inside the hole there was some greaze. Is this normal? Also I noticed that the structure of the intake was a little bit odd...take a look at this photo
I cleaned some of the grease so here is a better photo.
No, it isn't supposed to be that dirty. If it was that full of oil, you are sucking in oil into your intake (more than typical from oil injectors, and a properly functioning PCV valve). There are a couple places where that much oil could enter your intake. The first is a bad oil seal on your turbo compressor shaft. I have had this happen to me after a botched (not by me) turbo rebuild. You are having a large flow of oil going through your intake by the looks of things. This is backed up by your picture of oil leaking out of your turbine housing. First thing I would check would be to take off your compressor to intercooler piping and look down into the compressor housing. If it is full of oil, that is your source, and you will need the turbo rebuilt.
The second possibility is that you have either a failed, or improperly hooked up PCV valve. If it's hooked up wrong, it could be putting your crank case under vacuum and sucking out some oil under idle. I'd check the turbo compressor first
the plastic gasket that I have on. this is supposed to be better than the OEM one due to the fact that it is not letting the intake to get too hot.
IMHO, it is not make that difference. Should I keep this one on or replace it with an OEM one? I think that I have an OEM UIM to LIM gasket in my garage.
this is a vacuum line that I found plugged with a screw.
I don't know if this was plugged from the mechanic that changed the injectors last year. I found out that this plugged line goes between the lower fuel injectors and to the middle vacuum UIM nipple. I marked this line in the pic below.
Another photo of this line is below.
the plugged vacuum line that goes between the lower injectors
Here is a photo of my UIM. I noticed that there are 4 vacuum lines next to the water thermosensor but the FSM pic above shows only 3. Is this related to the plugged vacuum?
Here is a photo of all the vacuum lines under the UIM. I noticed that there are 4 lines that merge to 1 but the FSM does not show where these line should go. I can see that they go under the lower injectors. Any ideas?
Also, the back injector harness is attached to the injector with the help of a zip tie...this was put there by the guy who changed injectors probably. Could this be the source of the problem?
Here is the FSM pic. I marked the 4 lines that merge to 1.
1) some level of oil in the intake is normal and not cause for alarm. an older turbo is going to leak more oil, and the PCV valve will allow some oil to pass through (even when the car was new there was oil flowing there)
2) the 4 vacuum ports on the front - it depends on the model year of the intake manifold. I want to say the earlier models had an extra port, or was it the later ones? I'm guessing this is a euro spec left hand drive car so I don't know what differences were there.
3) the 4 to 1 hose splitter - those are for the oil injectors. They receive non vacuum (fresh air). Do not hook to vacuum.
1) some level of oil in the intake is normal and not cause for alarm. an older turbo is going to leak more oil, and the PCV valve will allow some oil to pass through (even when the car was new there was oil flowing there)
2) the 4 vacuum ports on the front - it depends on the model year of the intake manifold. I want to say the earlier models had an extra port, or was it the later ones? I'm guessing this is a euro spec left hand drive car so I don't know what differences were there.
3) the 4 to 1 hose splitter - those are for the oil injectors. They receive non vacuum (fresh air). Do not hook to vacuum.
thanks for your reply. I found out that the 4 to 1 are indeed the oil injectors but in another thread, Hailers I think, said that this line should be connected to the big vacuum port of the UIM -firewall side-. Can anyone confirm what is right?
Never heard of a metal LIM gasket... that would be neat to see. Either way, use paper gaskets
The diagram in the manual isn't completely accurate. They were likely made prior to final production and changes were made. I have corrected the diagram and highlighted what you are asking. The colors will match the pictures. Note that on the back of the UIM, what I have labeled AB1, AB2, and OMP, are all referenced to the same pressure source. That means AB1 and AB2 can be interchanged. The OMP spider has the big hose that fits on the big nipple. All 3 receive pressure from the same source in the throttle body. Only the bottom one, which you left connected goes to the thermowax system on the throttle body. That is because it does not receive pressure from before the throttle body, but uses vacuum from the secondary surge area of the UIM.
Never heard of a metal LIM gasket... that would be neat to see. Either way, use paper gaskets
I strongly recommend the metal one. The paper ones dont stand up too well with the heat. After I used one for the first time, I never went back, but to each their own.
*Edit: but now that im looking, I can only find one for a 6 port , bummer.
Thank you guys so much for all your help. So according to the diagram that Pyroman posted I have connected the proper way all the vacuum lines. So I will try to adjust my TPS because its way off now. I hooked up the TSP light checker and no lights were on.
I hope now that the TSP adjustment will be the final solution to my strange problem. I will update as soon as possible!!!! Thanks again! You RULE!!!
G.
Any updates? im kinda using your problem as a guide. im swapping out my injectors now. actually just wrapping it up. found my bov seized shut so i messed with it and now its seized open *smh* guess its a normal issue with the trumpet blitz.
UPDATE...
Desperation strikes again...
I adjusted the TPS by using the LED tester but the problem is still there. When I rechecked the TPS with a multimeter, I found out that the full range value (full throttle) is a little lower than the recommended 3.4. My value is around 3.24. Can this be adjusted somehow?
Reidnoa, probably my problem is not related to the injectors. I am suspecting a faulty control valve, a vacuum leak, a turbo problem, a faulty AFM, a faulty fuel pump or fuel pressure regulator...or something weird that I can't find!!!
Does anyone know if the double throttle valve can be related to my problem?
I will try to search again for vacuum leaks with the smoke method and I will update with any progress as soon as possible.
Not an update but...
I have also noticed that I can clearly hear a hissing sound coming probably from the engine bay while I am driving. I think that it comes from behind the dashboard. Are there any vacuum lines there? The stock OEM boost gauge line is located there?
This sound is not always present...it comes and goes and that's why I think that it might be related to a valve or something like that. Just another desperate thought...
So, I assembled a DIY smoke machine in order to search for vacuum leaks. I connected it to the vacuum port that feeds the boost sensor and I tapped the air intake of the UIM. After a lot of pumping with a foot air pump that the smoke machine uses, I found no signs of smoke or vacuum leaks. I also tried other vacuum ports in the front part of the UIM, no signs of leaking also. But I also noticed that the air pressure does not rise as Pyroman says in a previous post. So I tried to pump some smoke to the metallic vacuum lines that are under the BAC and feed the ACV. I used the middle one of the three and then smoke started to come out of the hole of the ACV. Is this normal?
Does this valve stay open when the engine is off? I also noticed that the vacuum line that I used (the middle one) goes to the third solenoid valve (blue one?) in the picture of post #64, right? So this solenoid vacuum line is connected to the fuel line, and I was wondering if this related to my problem. Should I just remove the ACV and used a block off plate like I did with the BAC? Just a thought...
Also I read that if I remove the ACV I have to install a vacuum port on the block off plate. Is this necessary? What about the 3 vacuum lines? Do I just have to tap them?
No that is not true, your car is not an N/A, that post was referencing the 5/6 ports that actuate in the upper rev range on N/A RX-7s. Think of something similar to V-tec on Honda's. Turbo cars are 4 port engines and do not have this feature.
No that is not true, your car is not an N/A, that post was referencing the 5/6 ports that actuate in the upper rev range on N/A RX-7s. Think of something similar to V-tec on Honda's. Turbo cars are 4 port engines and do not have this feature.
You should be fine to block off the ACV.
Ok. Thanks for your reply. I think that the removal of the ACV will only affect my idle, right?
I have been reading many topics today and I think that I have found something...
I read this topic (https://www.rx7club.com/2nd-generati...cv-work-89960/) and realize that my problem is probably related to the ACV and the 3 solenoids. The most suspicious one is the PRC solenoid (orange one) that according to the FSM troubleshooting table "shuts vacuum passage between dynamic chamber and pressure regulator". Also says "only when engine hot" so I guess that this probably the cause of my problem. Does anyone know how to check this the easy way?
Is it normal to hear a continuous clicking coming out of the solenoid rack when the engine is hot and shut off?
Thanks in advance.
07-08-20, 08:00 AM
, bummer.
