Escort Cosworth ST cutout
 

Hello,

I´m new here at the forum.:clap:

I have searched here for several times but was unable to find a complete answer.

I own a 4x4 Sapph which i love and a Escort Cosworth which i also love.

The escort is a car that was restored some years ago but hasn´t really been used, And when i bought i knew that it could still have some little things to be taken care of.

The thing is that the car is not boosting correctly and is cutting/misfiring, on boost.

The gauge states something like 0.6 bar of boost. It does not make any more.
This misfiring does not happen on the same situations. I can do a 70km/h-150km/h in 5 gear and it does not misfire, and sometimes in second gear it does.

Other times the inverse situation also can happen.

I´ve been said that it could be gasoline pressure, could it be?

It is really starting to annoy me because i have a Escort Cosworth that actually is slower than a Punto Multijet! :wall::wall:

Thank you!

Low fuel pressure could cause the mis fire as boost builds. Worth checking the whole fuel system and making sure the fuel pump is an original, has a clean filter with it and on the back of the pump. I would also chuck some new plugs in it and check they are correctly gapped.

Thank you Caddyshack!

As for as I know, these cars can be more tricky the big turbo ones!

It has a new fuel pump, filter, plugs, everything.

Can it be something electrical?

Probably worth getting the fuel pressure tested some how, it could be the regulator?

I am sure it could be electrical, is it still running standard management and distributor? The loom and earths could all need checking...just a case of check, check and check again.

I spent days on mine only to find that the hall sensor plug had come loose inside the distributor cap, I am running stand alone but the ecu still used the sensor....at some point I will blank off the dizzy and add a cam sensor on the back of the cam cover.

ST > What fault codes do you get from the EEC?

I Haven´t check for faulty codes yet as i´m now waiting to be booked at the mechanic.

Well as a fully restored engine, it might be intelligent to check all the plugs and sensors and everything.

One thing i did notice, sometimes when it misfires i get for an instant, the battery light on.

and when i´m at idle, the battery gauge goes a little bit down.

The car is all standard besides the exhaust and samco hoses!

So the engines been out and the alternator light comes on when it misfires.

Check your engine and other earths.

Check your alternator mounting and connections.

Well not always but many times it does!
It is not easy to see on these Escort dashboards! :?

Ok,

So I checked all the earth connections, etc etc, and today I did a test.
I disconnected the Amal/lektron whatever valve and tested it for both pressure and vacuum and it does not hold either one of them.

Then I connected the turbo pipe directly to the actuator and went for a spin.
The car does something like 0,5 or 0,7 boost but smooth and with no cutouts.
So I have a broken valve it seems.

The thing is, I can't find one for the small turbo cosworth and not even for the fiesta rs turbo. (I read somewhere that they are the same).

So what can I do?

Use a bleed valve? And disconnect the Amal valve?

Use a two or three port solenoid?

I'm biased here!

Another thing, when I unplugged the piping, and ran with the turbo pipe connected to the actuator, the battery gauge went up to a more acceptable place.

A different valve could be used, but electrical resistance of the solenoid would need to be high and EEC settings could need tweeking to suit characteristics of the new valve.

When you plug the lectron valve back in does the volts gauge drop again?

So i can´t just remove the valve and work with something just mechanical?

Yes it does drop again when i plug it back again. The weird thing is that i´ve just disconected it from the turbo and actuator and not the battery or the electrical conector of the valve!

You could do something mechanical. Don't overboost though.

Weird alright. I'd want to understand that before being satisfied the lectron was faulty.

But with something mechanical (bleed valve for example) how would I inform the ecu about the accurate boost pressure?

as for the valve being faulty, with the compression plus vacuum test and being it unable to cope with both, I got convinced !

You can use the VW N-57 boost solonoid to replace the lektron valve.
The plug is the same but they are 3 port so think you do away with the T piece.

And it can be from any vw car that uses the n57?

what do I do with the third port? Cover it?

and what about a thing like this?

http://www.lda.be/index.php?option=c...id=193&lang=en

With something like this I could ditch the Amal and control boost?

The EEC still has a MAF & MAP sensor.

EEC? Sorry don't know what that is !

http://www.escortrscosworth.com/forum/forum/technical-guides-information/technical-questions-servicing-help/41068-boost-control-amal-valve

i was trying to find out as not sure if he means he has blanked off a port on the N 57 or done away with the jetted ford T piece

https://cimg8.ibsrv.net/gimg/passion...c82f7c8bf7.png
https://cimg9.ibsrv.net/gimg/passion...f1d5f5848c.png

But if I use the t-piece, I will only have two ports sorted, the one that comes together from turbo and actuator and the airbox breather!

what to do with the other?

If the ecu allows it I can use a pipe from the actuator, one from the turbo and then the other for the air box

I need to try and find out what the guy did.
poss leave the airbox port open, keep the ford t piece and use the actuator bleed port to bleed back to the inlet manifold?

EEC as in EEC-IV. It is the type of ecu fitted to the ST Escos to control the engine.

Well i´ve just bought a electronic boost controller that has its own solenoid.

I hope that when i fit it, the problem goes away.

Does anyone know the oem boost for a small turbo escort cosworth?

I´ve seen a lot of numbers but not one conclusive, and as i´m running a standard ECU i don´t want the engine to detonate or have fuel issues.

There is not a single boost pressure number. It controls to a load map, so boost varies with RPM. The so called stage 2 chips run the injectors to 100% duty cycle, so the load map is configured to manage the maximum mass air flow and therefore keep fuel requirements from exceeding injector capacity.

I think fixing the broken part is preferred to bandadeing with an external boost controller.

Also don't think electronic controller is favoured over the standard lecktron valve as the ecu then loses the ability to cut boost if an issue arises.

Does the low pressure side of your lecktron valve vent to atmosphere or airbox etc?
You can check the valve by putting 12v across it direct and listen for a click.
ATM motorsport has used lecktron valves for £55