Fitted quads on 16v, now running on 2 cylinders??

[DaveW]

hey guys heres the problem,

i just fitted 20v quads onto my 16v and when i got to start it up it only seems to be running on cylinders 3 and 4? i get spark on all 4 cylinders, but im not too sure how to check if im getting fuel? when i pull the ign leads off 1 and 2 theres no change in the engines behaviour which is why i think its running on 2( that and its shuddering and carrying on like crazy...

its still the stock ecu which i know can run it (on the rich side) but using the stock ecu shouldnt cause it to drop 2 cylinders???

any help appreciated

dave

[oldcorollas]

swap injector wires around?

forgot to plug them back up?

does it smooth out at higher rpm than idle?

where and how are you taking the vac sense?

[takai]

Check that the injectors arnt clogged.

You are likely to get a lower vac signal with the quads. Mine was only 12mmHg rather than the normal 20mmHg, its now 6mmHg with the cams.

[DaveW]

swap injector wires around?

forgot to plug them back up?

does it smooth out at higher rpm than idle?

where and how are you taking the vac sense?

no inj wires cant physically reach the other injectors, it does smooth out a little, but blows a hell of a lot of smoke? im taking the vac line for the fuel pressure regulator from the small little black vac things on the top of each throttle, but ive also tried taking it from the line im using for brake booster which is a much bigger line and it made no difference...

[DaveW]

Check that the injectors arnt clogged.

You are likely to get a lower vac signal with the quads. Mine was only 12mmHg rather than the normal 20mmHg, its now 6mmHg with the cams.

how can i check that they arent clogged? and how could i go about checking that inj 1 and 2 are actually spraying fuel?

[oldcorollas]

is the smoke it is blowing fuel smoke?

if you pull the plugs are they wet? (try disconnecting the leads, then turning over, then pulling plugs. if they are wet, they are getting fuel)

can you feel/hear 1 or 2 inj clicking?

as for vacuum, if you are just taking directly form the TB's then it will probably be pulsing

connect all 4 hoses into something abotu the size of an NA fuel filter, and then maybe put a 1 or 2mm restrictor in the line comign from that to the ECU (or is it AFM?)

first tho, you can squeeze the MAP line (or the line to the fuel pressure reg) to restrict it. if it gets better, then you need a restrictor.

is it AFM or MAP?


if the MAP signal is less vacuum, then you have a double whammy.. ECU sees more load and injects more fuel... AND.. fuel reg sees less vacuum and raises pressure.. so you get extra fuel...


you could also try swappign injectors around and see if the problem moves.

[DaveW]

its map sensored. im using a line form each port on the T3 plate to make a line that runs from the MAP to all 4 ports, and likewise for a brake booster, ill try see if theyre clicking....

[oldcorollas]

run them to a chamber...

[DaveW]

ok so i just ran the engine, and put my ear to each injector and all 4 are def clicking, so that rules out faulty injector?... then removed ign leads 1 and 2 and let it run without them and turn it off, and pulled spark plugs 1 and 2.. both were dry. does that mean no fuel in cylinders 1 and 2? if so what could be the cause? low fuel pressure?

[AE35]

That would mean 1 & 2 aren't getting either spark or fuel or both.

Are the plugs wet with fuel?

Take a spark plug out, attach it to the end of the lead that corresponds with the spark plug you're removing and earth the plug on the motor and see if the plug is sparking while the car is running.

DO NOT touch the plug or you'll surely get a boot from the coil.

[DaveW]

yea already did that thats how i know im def getting spark, so now im pretty confident its cylinders 1 and 2 not getting fuel... however the injectors are functioning... does this mean it isnt getting the right fuel pressure? is that controlled by the vac operated regulator on the fuel rail?

[oldcorollas]

ok so i just ran the engine, and put my ear to each injector and all 4 are def clicking, so that rules out faulty injector?... then removed ign leads 1 and 2 and let it run without them and turn it off, and pulled spark plugs 1 and 2.. both were dry. does that mean no fuel in cylinders 1 and 2? if so what could be the cause? low fuel pressure?

ok, so all injectors opening.
both plugs dry = no fuel.

can you pull leads 3/4 and do the same? if they are wet, then you defintiely have an issue with 1/2 fuel only....

seems weird to have a rail blockage or injector blockage of 2 cyl at same time tho? hmm..

getting same voltage on all injectors? are they running thru resistor pack? all thru same fuse? if 1/2 had low voltage, they could click, but may not be holding open properly?

with the lower vac signal, if anything there would be more fuel pressure.. and all 4 cyls would be the same..

can you swap 1/2 and 3/4 injectors around and see if it is actually the injectors?
if it stays getting no fuel to 1/2 after swappign inj around.. then it comes down to elec feed to inj, or a weird rail blockage?

[DaveW]

yea i pulled 4 to check it against it and it seemed wet (although kinda oily wet...) so tomorro ill swap the injectors around to see what happens, and at the same time swap on my spare fuel rail to see if that fixes it... i might also try buy a fuel pressure gauge thing? and see what it reads?

[takai]

Shouldnt be the rail, the fuel feed is between the 1st and 2nd cylinders, so they should be getting fuel first.
Im guessing that the solenoids in the 1st and 2nd injectors are working but the pintles are clogged up.

[30psi 4agte]

Are these different injectors you are using ????

IE are they second hand injectors that came with the throttle bodys ? or are they the same injectors you have always been using.

Sounds like blocked injectors which would likely be the cause if they are second hand.

Swap the original injectors back in ?