ECU Link Error for OBD II

my car wont start... it cranks. but no firing

i know i need coilpacks. but i doubt that would keep it from even firing.

the car is a work in progress, but ran a few months ago?
it is missing a few check valves but it should fire! it did a few months ago. all i did was send in the ECU to get it chipped

now it wont link. there is no bent pins on the ecu or anything.
and i have sent it back in twice to be looked at.
oliver @ speedtuning says its fine

i tried to hook up my OBD and it says link error
it works on every other vehicle in my garage - Ranger, SLK, just not the A4. i dont get it?

any idea

Since you mentioned its a project car, is it possible that the car has been sitting for some time with a low/no charge on the battery? If so, maybe try disconnecting the computer for half an hour or so, then stick a freshly charged battery in there.

it cranks.... it just turns over and over. no firing. it has been sitting...

but it cranks. but like its getting no fuel

Getting pressure at the fuel rail? Have you pulled codes yet? Disconnecting the computer should reset it.

no codes. becasue it says link error? how do i check to see if my fuel rail has pressure?

and i have disconnected the computer mutiple times

There should be a schrader type valve somewhere on the rail. Cover it with a rag and push in on the center stem. The reason for the rag is that if there is fuel in the rail, and it is pressurized, it will squirt out. The rag should keep it from getting in your eyes, on your clothes, etc...

ok i pushed that in an no fuel is coming out of the rail.... the air bleed type vavlve at the end right? i remember i checked this long ago and it squirted. nothing is coming out.
 
the car has gas.
 
it was ran low a while back
 
what the heck is wrong?

Well, lots of potential problems, from the fuel rail back theres possibility of clogged lines, bad fuel pump, bad switch/relay that turns the fuel pump on, bad computer that tells the switch/relay to engage the pump, or bad wiring to/from any of these components. But, since you mentioned the computer is not responding to a code reader that works with other vehicles, I'd start there. You might be able to yank it and take it to a dealer for testing.

Actually, since you said you sent it in for chipping, are you sure you're reinstalling it correctly? All the wiring in the right places and whatnot?

its a simple disconnect.. reconnect. only two connections. and no bent pins on any of the connectors?  and the fuel pump fuse is fine. but at least i have it isolated down to a fuel pump/ fuel issue right?

Not if you aren't getting an OBDII connection. Has that particular code reader worked in the car before? These things seem a bit picky with the readers they will and wont work with. I returned two before getting lucky on the third, and ended up buying a VAG-COM cable anyway.

yah it work on my cousins 1.8t i tried.
 
i had a revelation.... if i turn the key to the on position. i should have a CEL come on correct
if i do not. My ecu is not talking with my car. i think i read that in a forum "paintballguy" said that he heard that from a tuner. i will try and find the thread
 
but if my car is turned on, i should have a CEL until its running. correct? if not. my ecu is the source....
 
 

Pull out all of your fuses and make sure NONE of them are blown, including the fuses NEXT to the ECM. If all of those are fine i would think the ECM is bad. In order to confirm that, you would have to remove the rear bench seat, take off the cover to the fuel pump and check for voltage at the pump when the key is on the on position. If voltage isn't there its probably a bad ECM because of the fact that you can't communicate with it.

ok, so i donno if this says anything. but the cooling fan comes on as soon as the ecm is plugged in. as soon as i unplug it the fan stops. but all of the gauge clusters stay lit and on.

and greaaaatt. now the car wont even crank. just turn the key.... and nothing. all the gauges are lit. battery is on the charger. no cranking now. it did a week ago. this is frustrating

how many fuses are next to the ECM. i saw one huge orange 40. is that the only?

bump. please help. still have issue

does the fuel pump cycle when you turn the ignition on? no connection to the computer/ECU = bad ground or ECU has died, try fitting a new battery then retry

with my car directly hooked up to another running vehicle. it wont even crank. but all lights illuminate. it doesnt even try. and fan comes on? still try new battery?
 
how do i know if the fuel pump is cycling?
 
i know the rail is not pressuring up.
 
i contacted oliver @ speedtuning and am sending him my ecu again to look at it.
 
what do you think?

does it have an immobiliser? of yes then you need VAG to reset it.
 
edit:- to hear the fuel pump cycle either get someone to turn the ignition key ( but dont crank the engine ) and you should hear it for 1 to 2 seconds then it shuts off ( all its doing is priming the system ) 

yes i do hear that. so that means my fuel system is priming? i ahve my ecu in a fedex box waiting to send out. should i hold off since my pump seems to be priming.
 
immobiliser? what would trigger it, and how do i shut it off. ever since i put my ecu back in. never started. it cranked, but no fire. now no crank at all

ok i just pulled all fuses again. and i must of missed this.

fuse # 38 [15A] _ Central Comfort Electronics

was blown..... would this affect anything?

all other fuses ok.
my car is turning on. beeping at me like the key is in the ignition like it is.
says push in clutch pedal to start
and i hear the fuel pump tick to prime

and i push in the clutch and try to turn it over to crank. nothing. not even a try. car still beeps and is saying push in clutch pedal to start

WTF!?!?! does this with or without the ECM plugged in. with the ecm plugged in. the radiator fan starts up and stays on???. thats it

could my coolant temp sensor be messed cus why is the fan coming on if the cars not even turning over.....

bump. sending out ecu to get looked at today.
and car is in the body shop. time for NEW PAINT :) will post some pics

ecu is back and in. CEl is now on with key in accerssory. and fuel rail is pressured up. so thats goos! but
 
 car wont turn over tho, my immobiliser light is flashing?