I just finished replacing all of the vacuum lines, gaskets, and one way valves check on my FD. Just came back from my first test drive and I am not impressed. I can hardly make 7 lbs of boost, major hesitation or sputter at 2,800 rpm. Seems to work ok after 3,500. Can someone point me in any direction? Is it possible that I now have a 3,000 hesitation issue?

 

Search button is your friend. Good luck sorting out all the shitty threads just like this one that now clutter up the good posts.

 

So, in your 1,489 posts Mr. No life, you never posted a shitty thread. Great to know we have someone who is perfect on this forum. I thought this forum was meant to help other FD owners.

 

I feel your pain. I've pulled out the manifold on 3 separate occasions to fix a boost problem and I finally got it right on the 3rd go.

There's nothing worst than spending countless hours trying to fix something, putting it all back together only to find its not fixed.

Are you getting proper boost patterns after 3500rpm? Or still 7?

Second turbo kick in at least?

 

That's not the 3k hesitation.

Do you have all of the stock emissions components? Did you have your injectors serviced? (How long since you ran the car?)

Dave

 

Did you also replace the vacuum lines on the turbo actuators?

 

Thanks all,

The car has not run in 1 month. I never had the injectors serviced (only 34,000 original kms) and I did not change the lines to the actuators (no hoist). I will take it back out for another spin and get my wife to look at the boost pattern.

I cleaned all the grounds and found a pinched vacuum line that goes to the catch tank. Fixed the kinked line and no difference. How long should the vacuum tank hold vacuum (the one right on top of the engine)?

 

Did you replace these lines (the ones with the colored dots)?

 

The vacuum tank should hold vacuum almost indefinitely.

I asked about the injectors in case you were having a primary injector problem. Sometimes draining the fuel rail and letting them sit causes problems, other times the actual cleaning process makes things worse rather than better.

Keep looking for pinched/damaged hoses, and make sure your check valves are pointing the correct way.

 

Yes, I did replace does 2 lines and carefully removed and reinstalled the restrictor pills. Is it possible that I put them in backwards? Or does it make a difference?

Dave, the reason I asked about the vacuum tank is when I removed the line this morning, I did not have any pressure...I will try again tonight after the car sits for a while. I did start the car up and had it run for a while when I removed it then, there was pressure.

I also removed the 2 bolts that hold down the primary injector so I could get at one of the vacuum lines. Could moving them cause some of my issues?

 

Just got back from road test and here are the specifics:

16 - 17 inHG at Idle
hitting 3 - 4 lbs of boost at WOT in neutral
boost pattern in 3 rd gear WOT 9.5 lbs at 3000 rpm, 6 lbs at 4500 rpm and drop off to 4 lbs till red line

I also have a major hesitation or miss at 2800 - 3000 rpm. I can also smell fuel.

 

With that pattern, your restrictor pills should be fine. I would start by verifying you have your check valves in the right direction allowing the pressure to hold where it should be...

 

Scrap the car!

thats what i feel like doing every time i have trouble with boost

Sorry for the unhelpful post! Only thing i can say is check the little flapper that shuts the secondary turbo off on the Y pipe is hooked up correctly.

Its probably going to be one of two things, that flapper - or the door in the manifold that shuts the secondary turbo off is stuck shut.

check these two vacuum circuits first... Look at the diagram to see which i mean, theres an actuator that bolts to the top of the Y pipe - check that. Theres another one that bolts to the exhaust manifold, right underneath the car - check that isnt hooked up backwards or similar.

Bob

 

So hypothetically, if one or both the actuators were stuck, would they need to be replaced, or do you just need to yank on the rod?

 

Parallel!!

 

Only if you lost track of the black plastic spacer underneath the primary block.

Since you smell fuel I recommend pressurizing the fuel rail per the test procedure and searching for the fuel smell. Leaking fuel is very dangerous.

This is saying nothing of the boost issue. It sounds like a separate (and much less important) problem.

Regarding the boost, is the check valve on the pressure chamber pointing *toward* the pressure tank?

 

I have checked all the check valves and they are all pointing in the right direction. There was no pressure in the tank again when I disconnected it, I will order a new one tomorrow. If the pressure tank was leaking, would this cause the boost pattern boost pattern in 3 rd gear WOT 9.5 lbs at 3000 rpm, 6 lbs at 4500 rpm and drop off to 4 lbs till red line?

 

It may however unless you actually see a problem with the pressure tank it's probably not the fault. The hoses and check valve are also the problem.

Any headway on the fuel smell?

Dave

 

Hey Dave.

Thanks, the check valves and hoses are brand new...defective valve maybe?

No headway yet...I will pull off the intake in the morning and have a look at the injectors. Should I replace something while I am there? New 'O' rings maybe?

I can really smell the fuel when the car his hesitating at 2800 rpm...feels like bad plugs ( I know has I had them replaced 5k ago for miss at hwy speeds under load.

 

Test your fuel system like this:

https://www.rx7club.com/showpost.php...&postcount=255

If you have a leak, you'll easily see it.

 

Found part of the problem...one of the rubber O rings went sideways on one of the primary injectors. Just finished removing it, it was actually in 3 pieces (I used a pick and the Shopvac so no pieces would fall in).

Do the air bleeder socket insulators need to be replaced ( I have them on order)? If so, any idea on how to remove them? I tried and they are not coming out easily.

Thanks,

 

Anyone, does anyone have a trick on how to remove the air bleed sockets...I have attempted and I am starting to scratch the coating on one of them.

 

sorry i got a similar problem (my boost pattern 10-8 and the drop to 5- i have written separate post for it https://www.rx7club.com/3rd-generation-specific-1993-2002-16/vaccum-hose-replacement-problem-771186/ )

but someone here mentioned check valves directing wrong way - i got viton check valves from Dale clark -how should they be directing>? has anyone got a pic?

 

I ALWAYS replace the injector insulators. Lube them up with something like WD40 so that they do not tear when inserting the injectors. The air bleed sockets or atomizers can be removed with a hooked pick. Sometimes they break so have a strong vacuum cleaner ready to suck out any pieces that fall into the intake ports. Make sure you start with an empty vacuum cleaner and make sure you find ALL the parts if anything falls in.

 

Update - Had the UIM off for the second time. Found 2 pinched hoses from vacuum line job. Had leak from primary injector insulator leaking causing my fuel smell and miss at 2,800 RPM.

Also installed additional grounds - car idles smoother now and seems to have better throttle response.

Still having a problem with boost pattern in 3rd gear WOT - 9 - 8 - 6. I can also hear a siren type noise after easing off the throttle. Any ideas?