*update* throttle bodied car wont start

[BertieG]

just fitted a set of newman PH3s, GSXR throttle bodies and a predator ECU mapped for an engine of similar spec. have fuel and spark, but the engine will not start. turns over fine, occasionally sounds like its about to fire, but will not go. tried changing the cam timing a bit with no change

anyone got any suggestions as to why it wont run?

[Olly]

Have you zero'd the tps

[BertieG]

Have you zero'd the tps

explain?

[Ryan]

Was going to say check TPS.

Unplug the TPS on mine and its interesting trying to get it to run.

[BertieG]

its running the suzuki tps still. ive pulled the individual wires through the plug and pushed them onto the plug on the suzuki tps. do they plug in in the same order?

[jeffchiz]

when mine wouldnt start after fitting bodies, we weres tumped as fuel was coming down the pipes but wasnt being injected, we ran a bit of sand paper over the terminals to the injectors and it started straight away

a car should start without the tps being calibrated mine did, just meant i was idling at 4kprm lol

[coleman258]

Sorry for noob question and thread hi-jack, i allways read about the TPS being calibrated, how do you do this?

[jeffchiz]

Sorry for noob question and thread hi-jack, i allways read about the TPS being calibrated, how do you do this?

well on the software ive got on my laptop across the top click on one of the tabs and it says calibrate TPS, then you take a reading for when its closed and reading for when its fully open so it knows what 0% and 100% is, takes 10 seconds to do when the laptop is connected

[BertieG]

when mine wouldnt start after fitting bodies, we weres tumped as fuel was coming down the pipes but wasnt being injected, we ran a bit of sand paper over the terminals to the injectors and it started straight away

a car should start without the tps being calibrated mine did, just meant i was idling at 4kprm lol

checked the plugs and they had fuel on them, so it must be getting injected okay

[K567]

2 things to suggest
1 check coil/leads are running correct firing order
2 ECU/crank sensor

[BertieG]

2 things to suggest
1 check coil/leads are running correct firing order
2 ECU/crank sensor

coilpack, so cant fuck that up! its sparking, so crank sensor must be okay

[K567]

getting spark and fuel has nothing to do with it if its firing in the wrong order ( ecu or crank sensor related )

Question, I don't know french cars too well, newbie on these, but does the VTS utilise a cam sensor ?

or and i have seen this before

your 180deg out on your timing

[BertieG]

getting spark and fuel has nothing to do with it if its firing in the wrong order ( ecu or crank sensor related )

Question, I don't know french cars too well, newbie on these, but does the VTS utilise a cam sensor ?

or and i have seen this before

your 180deg out on your timing

no cam sensor on them.

the timing is something i had considered, so might have to check it. how could i tell if the timing is out? would it be one camshaft or both?

[K567]

it could be any.

easy way is to take plugs out, use socket/wrench to rotate motor 4 times bottom end ( clockwise ) use locking pin to lock at tdc and then check cam locking points line up correctly

this is the most unlikely reason but i have seen this before and to be honest its a total noob mistake when following guides to install cams

I'm still leaning more to ecu related

someone else who knows the predator a little more might need to step in here

but because the ecu is plug n play ( standard engine wiring harness ) have you tried plugging your stock ecu in to see if it will start off that

[BertieG]

With the standard ecu its exactly the same, sounds like its about to start but won't go. I can't imagine the timing is out, because it sounds okay turning over, would it not cough and backfire etc if the timing was 180 degrees out?

[saxova]

Sound's similar to my problem after I put a 16v in my car.

Turned out to be the injector's not firing properly, because 1 of the clips was loose. And it would spray fuel randomly - I took them off and replaced clips, Then they sprayed every time.

[BertieG]

the more i think about it the more i lean towards the TPS. i have no idea how to wire it in, any information i found online seems to use different coloured wires to what i have

[BertieG]

just had another look, and tried again with the standard ecu, and it runs! idles rough as nails at 500rpm, but it will idle for a few moments okay. soon as you give it some throttle it cuts out, but thats to be expected

when i stick the predator back on, it wont go at all. big difference is you cant hear the fuel pump priming with the predator connected, but you can with the original ecu connected

[Tom5190]

predators dont prime the pump before you turn the key thats why you dont hear it

[BertieG]

so what would cause it to run on the original ecu, but not one mapped for the job?

[jeffchiz]

think you need to contact andy with this problem, i was stumped by not hearing the fuel pump priming as well lol

[K567]

have you got a volt meter?
you can check the wiring on the TPS and find the plus/ground/signal wires
then compare them to the predator wiring diagram for the TPS

[BertieG]

have you got a volt meter?
you can check the wiring on the TPS and find the plus/ground/signal wires
then compare them to the predator wiring diagram for the TPS

a very pikey voltmeter. tried testing the TPS but i couldnt get any kind of reading from it, so might have to see if i can borrow one from somewhere

the TPS doesnt explain the fact the car will start on the original ECU but not the pred though does it?

[K567]

Are these the colours you have

this is suzuki TPS wiring

Bl (Blue) Positve
Y (Yellow) Signal to ECU
B/Br (Black w/Brown) Negative

[K567]

and if i read the diagram right on your saxo

pins on plug

a = Positive
b = Ground
c = Signal

[K567]

so if its stock suzuki wiring its all wrong

and you'll need to swap B and C

use voltmeter to confirm wires

you'll find a +12v
a gound
and a wire when ignition is on that will vary between 0 and 5v as you open throttle

[K567]

my thoughts are
if your on neg on the signal wire the std ecu will fire as it see 0v with crappy fuel as you open throttle it will just not add fuel lean out massively and cut out

[BertieG]

the suzuki TPS has no wires, a plug should go straight into it. seems odd considering all the information i have found on it talks of the colour of the TPS wires

what also seems odd, is that the saxo wiring has one yellow/green wire, and two white wires. id have thought that meant one ground wire and two signal wires, as those colours often indicate. yet the yellow/green wire was located at A, where the positive should be

[BertieG]

just had another gander with the voltmeter, and managed to achieve some kind of reading between B and the battery earth, and between B and A. so im pretty sure A is ground and B is positive, making C the signal

[K567]

its defo 1 signal a ground and a pos

can you bodge the the saxo TPS on to try it?

[BertieG]

its defo 1 signal a ground and a pos

can you bodge the the saxo TPS on to try it?

unfortunately not, as the throttle body connection is too small to turn the saxo TPS

[K567]

well at least you have the right wires now try that.

[BertieG]

well at least you have the right wires now try that.

gave it a go, made no difference with either ECU

[jeffchiz]

as i said earlier my tps wasnt calibrated AND wired up wrong but my car still started, i was drving arond for a month or so wasnt until i drove it to pug1off they wired it up right and calibrated the TPS, tbf it did drive like a bag of wank

[K567]

OK last option for me is: -

uplug and clean the entire engine harness

double check every connection

[BertieG]

ive narrowed it down, its definitely something to do with the TPS. i refitted the saxo TPS to the loom, left it off the bodies and tried twisting it with a screw driver whilst starting, and for a moment it would start and run. a mixture between adjusting the cam timing slightly and getting the TPS sorted should do it

[RyanSaxo]

ive narrowed it down, its definitely something to do with the TPS. i refitted the saxo TPS to the loom, left it off the bodies and tried twisting it with a screw driver whilst starting, and for a moment it would start and run. a mixture between adjusting the cam timing slightly and getting the TPS sorted should do it

it ran on the pred with the above tweak??

weird that it would run on standard ecu and not on the pred - makes me think that something on the pred map isn't right?

[BertieG]

it ran on the pred with the above tweak??

weird that it would run on standard ecu and not on the pred - makes me think that something on the pred map isn't right?

just about idled for a moment on both ecus, but wont rev up or stay idling on either

[Bcup]

Check the pins on the car ECU plug.

[BertieG]

Check the pins on the car ECU plug.

checked that before, all intact, none bent or snapped (that i can tell anyway)

[Bcup]

And the relay that is located under the ECU.
Have you check that?

[BertieG]

definitely havent unplugged it, but i will have another look at some stage to check its located properly

[BertieG]

it runs!

the 4 bar FPR doesnt seem to be flowing enough fuel. plugged the fuel line straight into the fuel rail and she fired up instantly. sounds fantastic :)

[K567]

4bar be plenty, sound more like the 4bar is knackered and its not making pressure.

which way have you got the rail running, you know FPR is post rail not pre rail?

i wouldn't recommend running without regulator

just to check you do run a fuel return right?

[BertieG]

4bar be plenty, sound more like the 4bar is knackered and its not making pressure.

which way have you got the rail running, you know FPR is post rail not pre rail?

i wouldn't recommend running without regulator

just to check you do run a fuel return right?

its not finished and back together just yet, ran out of time so was just happy to hear the engine running

i'll carry on with it maybe tomorrow (my birthday, so maybe not) or friday and make sure i get it running properly. need to cut the throttle cable down, tidy wires up, refit trim etc and adjust timing before im 100% happy

[K567]

happy Bday for tomorrow mate
mine on friday lol

whens there gonna be a vid/pic post

[BertieG]

got everything connected and ran it up and down the road. bogging down a treat when you put your foot down, also very very jerky and low speeds. would slight cam adjustment cause/fix this?

[K567]

Probably over fuelling more than anything

[Heftydanielson]

Might be tempted to drive to Exeter to have a little look. Sounds good.

[BertieG]

Probably over fuelling more than anything
did also wonder that. seems find between 2.5k and 4k, just not particularly happy either side of that. cant plant your foot, have to slowly build the revs up too.
Might be tempted to drive to Exeter to have a little look. Sounds good.

if i get it running smoothly then i'll definitely take you out for a little spin :y:

[Sophia_Bush]

I assume the map on the ecu is to a similar spec Bertie? in my experience of these they will still need a map tweak to get it to run better, also have you set the tps up properly? on these ecu you need to setup in tunerstudio the mapping software it's dead easy and takes about 5 min provided you got the right cable

[BertieG]

I assume the map on the ecu is to a similar spec Bertie? in my experience of these they will still need a map tweak to get it to run better, also have you set the tps up properly? on these ecu you need to setup in tunerstudio the mapping software it's dead easy and takes about 5 min provided you got the right cable

the map is for an engine with these exact bodies, same cams and a similar exhaust. i realise whilst it wouldnt be spot on, it should be close

i have wondered about fiddling with it with the mapping software. i'll invest in a cable and give it a go

[luthor1]

Fuel pressure needs to be measured as identical to the car the MAP was for, in order for the MAP to be close

Andy

[BertieG]

plugged my laptop into the predator and its giving some odd readings. it will only give a TPS reading with the engine running. any idea why this is?

[Sophia_Bush]

should be able to set tps when the engine is off but in 2nd click pos iirc

[BertieG]

should be able to set tps when the engine is off but in 2nd click pos iirc

thats what i thought, based on a google search. no reading whatsoever from the TPS until i run the engine, when it starts going mental

[K567]

sb is right you should be able to read from all sensors in one way or another when full ignition is on but not running ( point where all dash lights are on )

if not then back to volt meter and check tps readings at tps then check again at ecu ( you'll need wiring diagram of pin outs to ecu )

if predator runs as std you may need to confirm this it should 0 to 0.6/8 closed ( depends on idle screw pos if there is one ) and +5v open

[BertieG]

for this kind of job i really need a better volt meter, the accuracy of mine is truly shocking

[BertieG]

thinking about it, it cant be a dodgy sensor, as i tried it with the original citroen sensor with no change

[K567]

yeah but you did it with a screwdriver not on tb

have you got the wiring right now for the bike tps?

and have you used the software to calibrate tps? <- it might just be this???

[BertieG]

yeah but you did it with a screwdriver not on tb

have you got the wiring right now for the bike tps?

and have you used the software to calibrate tps? <- it might just be this???

i just meant plugging the TPS in to see what reading i got. no reading whatsoever, no matter what position the TPS was in. doing it like this i can 100% rule out the possibility of the wires being in the wrong order, although im pretty certain i have the wiring correct for it

i cant use the software to calibrate it without getting a reading from it at closed and wide open throttle. thats the problem im having with it

[K567]

then theres gotta be something wrong then mate

as soon as engine harness has power it should read at the ecu id check with predator on this

engine doesn't need to be running to get signals, and if when its running your getting random signals

pm me your number mate ill give you a call if your working on it now easier to explain

[luthor1]

with the laptop plugged in to the ECU and correctly connected and configured, and the ignition in position "II", then the ECU software will 'come alive'.

I am confused when the OP says TPS is not showing anything, is the WHOLE laptop display greyed out or is the ECU powered up and clearly showing live values for things like Coolant temp and air temp?

Andy

[Heftydanielson]

Do you need me to come up there with a hammer and a role of ducktape to get her working? Good old Halfords style. x)

[BertieG]

with the laptop plugged in to the ECU and correctly connected and configured, and the ignition in position "II", then the ECU software will 'come alive'.

I am confused when the OP says TPS is not showing anything, is the WHOLE laptop display greyed out or is the ECU powered up and clearly showing live values for things like Coolant temp and air temp?

Andy

tunerstudio doesnt seem to be that happy in general. keeps popping up saying something along the lines of "serial signature required" if you open a new project. it gives the option to connect anyway, although i have wondered if this is why im getting some odd readings

[luthor1]

Do you want me to sort it out remotely for you? I can probably do it one evening this week if you can get wireless and power out by your car, say wednesday/thursday night?

Andy

[BertieG]

Do you want me to sort it out remotely for you? I can probably do it one evening this week if you can get wireless and power out by your car, say wednesday/thursday night?

Andy

if its not too much trouble, that would be fantastic help mate :y: