0c00l

So My 03 coupe had some trans and engine issues mainly pilot bearing and throw-out bearing on the manual trans and engine was ticking so I found a 4 door donor for 250. The donor ran and drove zero issues. I pulled the donor and swapped, everything went smooth but the donor header had no O2 sensor bung and I wasnt using the down O2 sensor anyway, so after the swap I had no O2 sensors plugged in. The car started right up and ran for about two weeks, now it wont start, fuel pump is good. It turns on for two seconds then shuts off as it is supposed to. The relays click and have been checked with multi meter, also I swapped the ECM/PCM just for giggles and same thing. If I pour fuel into the throttle the car starts and runs at idle so it seems to get some fuel,as soon as I give it pedal it dies. Is this all because of the O2 sensors?

I plugged in a Bosch ODB1300 and got no codes but jumping 4 and 9 on the cars ODB2 plug I get a ton of flashes so I know its throwing CEL's.

bbarbulo

You do know that >75% throttle opening is 'flood clear' mode and injectors won't fire.

Also, you know that you need a crank position sensor feedback to tell the ECU that the engine is turning over and to start firing injectors to deliver the fuel.

So, step 1:

What is your fuel rail fuel pressure?

Step 2:

What is the TPS saying % open?

Step 3:

What is the Crank Speed while cranking the engine (as far as the ECU is concerned)?

You say the car runs if given fuel, so I don't REALLY suspect a CKP/CKF issue since those are used for ignition timing, but having you test it all should at least teach you something. Cuz you're not far from knowing nothing.

0c00l

When trying to start I never opened the throttle. The CPS is plugged in, I dont have a fuel pressure gauge (guess I could rent one) although pulling the hose off and put it in a jar and when I turned the key to on it did pump gas. The crank speed sounds the same remember the car did run it just stopped all of a sudden.

bbarbulo

I never said you did. But the ECU certainly could think you did.

You clearly stated you have CEL codes. Well I'm telling you that code will point you to either the Throttle Position Sensor or the Crank Position Sensor. Get a scan tool that will pull the codes for you, it'll make your life easier.

It seems you have fuel at the rail, but the ECU doesn't see the engine cranking (and therefore will not open the injectors) or the ECU sees the throttle wide open (and therefore will not open the injectors).

In either case I give you things to check so you can get the car running. If you don't want the car running, please continue to assume 'plugged in' means 'working'.

0c00l

Update/ So I got my hands on two different OBD readers and one does live stream data. There are no codes showing for either, rpms go up to about 195 when trying to start which shows the Crank sensor is working. I still havent got my hands on a fuel pressure gauge (I will asap) but I did find that my car is equipped with a Inertia Switch for the fuel so if the car flips over it will shut off fuel, mine was not mounted so I did put it back in its place and still no start. Could it be stuck in protection mode? When reading live stream data the fuel sys1 is showing "open" and I thought that when starting the car it starts in closed loop, until the car starts?

JPat

First i dont think its a good idea to jump terminals on your ObD11 Plug. Mabye iam wrong, someone will need to confirm.

Also, i wonder if the ground on the TStat is bad.

This problem shouldnt be the sensors, altho if you drove long enough your cat could be dead and plugged. But i doubt it.

With any engine swap you gotta look for
chaffed wires,
pinched wires,
pulled wires,
broken plugs,
loose grounds,
dirty grounds

0c00l

Thanks for the reply, on the em2's the #4/#9 are the way of getting cel's manually. The Cat was deleted but I have both 02 sensors up and down back in and tested fine. All Grounds have been gone over very carefully.

0c00l

Update, it was the head gasket. Car turned over, has spark, had fuel, no compression! Just weird because it ran fine a week earlier!

Thanks for all the responses, I got to remember to check all those things next time.

JPat

Thanks for the update! sorry to hear.

JPat

Thanks for the update! sorry to hear.