Toyspeed.org.nz Message Board

by **maxium** » Mon Nov 06, 2006 8:18 pm

hey all
my freind has a escort race car and has fitted a 20v blacktop in to it, hes a tig welder and has done a mint job of the whole job but after 4 different mechanics and auto sparkys looking at it he still cant race it as when the throttle opens the engine runns like the rev limiter is on, the only way to make it rev is open the throttle really slowly
from what i understand it has a standard rewired computer and standard ignition aslo has quad throttle body on it with a map sensor hooked to vaccum from all the ports, they have just about repalced every bolt on part on the engine to fix it but no one has sorted it yet, any help would be great as i think hes had enuf of the whole thing cheers

by **AE82 FXGT** » Mon Nov 06, 2006 8:21 pm

Random guess from me says TPS

by **demis** » Mon Nov 06, 2006 8:37 pm

i would also say the TPS or map sensor

by **maxium** » Mon Nov 06, 2006 8:49 pm

thanks guys any idea wot to look for in the tps? or map? im just finding out exactly what sorta 4age it is for everyone

by **AE82 FXGT** » Mon Nov 06, 2006 9:09 pm

TPS should be running off one of the throttles I guess.
Not too sure with quad throttles.

As for the map sensor, follow all the vacuum hoses coming of the manifold, and find where one goes to a little box that has 3 or 4 wires coming out of it, I think. It'll probably say vacuum or map sensor on it.

by **maxium** » Mon Nov 06, 2006 9:51 pm

update
i was wrong its a 94 20v blacktop has been rewired, engine was a runner before a auto sparky rewired it now it wont rev just revs like its on the limiter but it aint. it idles fine will rev if you open the throttle very slowly,
any one out there have a wiring diagram i could have a look at? its got a map not airflow meter if this helps
many thanks

Website · by **Rick** » Mon Nov 06, 2006 10:14 pm

maxium wrote:update
i was wrong its a 94 20v blacktop has been rewired, engine was a runner before a auto sparky rewired it now it wont rev just revs like its on the limiter but it aint. it idles fine will rev if you open the throttle very slowly,
any one out there have a wiring diagram i could have a look at? its got a map not airflow meter if this helps
many thanks

Whats the bet your mate is not running the factory plenum chamber and running trumpets???????

by **l1ttle_d3vil** » Mon Nov 06, 2006 10:21 pm

my 16v 4age had these sort of problems when it had dodgy distributor wiring...check the timing etc. mine was changing every time I started the car...

by **maxium** » Tue Nov 07, 2006 5:25 pm

thanks guys , um it has a custom plendum. could it be sum sorta cock up with the wiring when the loom was redone for the escort

by **johntramp** » Tue Nov 21, 2006 3:03 pm

hey did you get anywhere with that problem? I have the same thing happening with my blacktop

Rick, what does not running the factory plenum chamber and running trumpets do to cause this? I have the engine in rwd so no plenum

by **johntramp** » Tue Nov 21, 2006 9:03 pm

could blocking this vacuum line be causing problems with the map sensor?

by **sergei** » Tue Nov 21, 2006 9:54 pm

The blocked line is for idle control valve.
Better to unblock it otherwise it will run like crap on cold/idle

by **johntramp** » Tue Nov 21, 2006 10:33 pm

when I didn't have that blocked it was idling high, and I have this line for idle, it seems to sit nicely on about 800rpm

my problem is above 3000rpm, so you don't think that line could be causing it?

cheers

by **sergei** » Tue Nov 21, 2006 11:37 pm

Your car was Idling high due to vacuum leak, because of the vacuum leak you have performance problems.
This is wrong way of fixing idle.
Put that filter onto the line where you have bolt pluged in. The line where is the filter is connected is for powersteer idle up. it can be blocked.
Make sure you have all the lines hooked up or unnecesery ones blocked (only P/S, purge, and A/C). Make sure you have 2 check valves on the vacuum booster lines (there are 2 of them), "Y" or "T" them only after check valves. On your picture brown hoses with brass T connector are the vacuum booster lines (for brakes), which are connected wrong and might lead to performance issues.
With all the lines connected and idle control valve unbloked you should get ~1500rpm on cold and ~800rpm on hot at idle. Only one hose should suck air in and that hose is from idle control valve. If you have any other hoses sucking air, make sure it is connected where it supposed to be or blocked.

Pleniums on 20v do not make any difference - it can be any shape and size (as long as it is not restricting flow) or missing at all, it should not effect the performance in such extreme way.

by **johntramp** » Wed Nov 22, 2006 2:14 am

Hey, thanks for explaining that sergei. So the valves are to stop vacuum leaking between the two separate lines? Is there any specific valve I should look out for?
Also, do you know what this line is?

Cheers

by **sergei** » Wed Nov 22, 2006 7:47 am

You should use brake booster valves (normally cars have 1 but 20v need 2).
That line is for purge system coming from charcoal box. If you don't have charcoal box block that line, if you do connect it to top of it. Charcoal box is big black plastic cylinder which has line coming to it from fuel tank.

by **matt dunn** » Wed Dec 20, 2006 10:57 pm

Did this car come to Timaru to get fixed or a link fitted?

If so i think i have worked on it.

by **johntramp** » Thu Dec 21, 2006 12:17 am

no, it has a factory ecu which I put in and wired up with help from sergei

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20v black top wont rev help

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