Idle and air pump issue

[mangiavelox]

Hello everybody,

I'm a new owner of a fd3s from 1992. I purchased the car for a very good price with a engine rebuilt 10 years ago and no more drive after the rebuilt. I took the car with the engine lo running, i just swapped the fuel pump and swapped all the fuel with shell 100 and the engine started, but don't drive very good.

I checked the compression with a normal tool for piston engine and the compression is very good.

The engine start fine but the idle is high and I have a strange issue. Some time the air pump stay always on since some rpm, some time off and some times on/off.

I attached a video to explain better the issue

 

[Spendyrx]

Check yor map sensor pipe mate. Start with the basics

 

[Spendyrx]

It does sound more like a vacuum leak though tbh. Maybe check things like your brake booster pipe. Anything that will draw air into the system! That usually creates high idlevel.

 

[mangiavelox]

It does sound more like a vacuum leak though tbh. Maybe check things like your brake booster pipe. Anything that will draw air into the system! That usually creates high idlevel.

With your reply I just remember that I have the brake pédale come harder when I rev... I need to find the leak from the big hose or from the small 6mm?

Sorry but what is the tbh?

 

[mangiavelox]

The other issue is that the engine rev very slowly and the car as not power

 

[Spendyrx]

Haha sorry mate I didn't realise you are Swiss! Tbh is just abbreviated lazyness on my part. It stands for 'To Be Honest'!
I would check the hose that runs from the master cylinder to the upper intake manifold.
Not quite sure what causes a slow rev, I'd assume maybe something like the throttle body butterflies aren't opening fully? Get a mate to put their foot on the accelerator pedal and check to see if the wire is pulling the throttle fully open!
I'm sure there'll be plenty more people throwing in some answers soon too

 

[Jit]

We need more videos to see what you mean.

Check that there is a one way valve in the hose that goes from the UIM to the brake servo

In your video of the air pump, are the revs (rpm) steady? The air pump clutch will cut out at 3000rpm. It’s not engaged all the time

 

[mangiavelox]

Haha sorry mate I didn't realise you are Swiss! Tbh is just abbreviated lazyness on my part. It stands for 'To Be Honest'!
I would check the hose that runs from the master cylinder to the upper intake manifold.
Not quite sure what causes a slow rev, I'd assume maybe something like the throttle body butterflies aren't opening fully? Get a mate to put their foot on the accelerator pedal and check to see if the wire is pulling the throttle fully open!
I'm sure there'll be plenty more people throwing in some answers soon too

No problem, thank you for your advice. tomorrow I will check that but this hose is unplugged, before the last owner has plugged a boost gauge on it and I just insered a bolt Inside for test the engine...

 

[mangiavelox]

We need more videos to see what you mean.

Check that there is a one way valve in the hose that goes from the UIM to the brake servo

In your video of the air pump, are the revs (rpm) steady? The air pump clutch will cut out at 3000rpm. It’s not engaged all the time

Tomorrow I will make more videos.

In this one the rpm are between 1400 and 1600 steady. Yes the air pump cut out at approxymatly 3000rpm

 

[Jit]

In that case you need to look at the circuit controlling the air pump. Or try another air pump and see if it does the same

 

[Spendyrx]

Haha that's probably why you are getting a heavy brake! You should see 3 pipes from your upper intake, one that goes to your crv (air filter/intake are) that's closest to front of car, one in the middle should have a bung (I used to use that for my boost gauge) those 2 are something like 3 or 4mm pipes then the closest to bulkhead/firewall is about 10mm in diameter..... this should be connected to the brake master cylinder and as jit states, it should have a check valve in the hose. If you blow into it you will only get air passing one side. It needs to be entering into the upper intake manifold and not being able to return to the brake master cylinder. Hopefully it's that and it'll be a nice easy fix for you mate