wont start questions

[Samiam1017]

well I tried to start my engine for the first time and it cranks but doesn't start. I checked for spark and fuel and I have everything. I don't think it would even crank if it was security. I did eliminate all of the smog,cold start, tvg stuff and have CELs for that also low voltage for coolant and knock sensor CELs. would these prevent a start? I don't see why? also I don't have a accessport yet as I wanted to make sure my w iring was correct and engine started before I bought one because if it didn't I was gonna go with an AEM standalone. any things I maybe need to look at or missed? the wiring and ecu are 07 wrx. thx in andvance for all your help

[JeromeS13]

It's possible that it could be the security. Are you using the corresponding key, ecu, and control unit? Do you have the antenna connected and in the correct location (around the key cylinder?

It could also be the crank position sensor and a few other things... Can you verify fuel pressure?

[Samiam1017]

I do have the correct key,ecu control unit and what ever else its all from the same donor. I don't have the antenna connected so its not around the key?? I don't remember this from the donor ill have to search pics to see exactly what is there.. I don't have a fuel pressure gauge I should install one as I have a adjustable regulator

[JeromeS13]

I do have the correct key,ecu control unit and what ever else its all from the same donor. I don't have the antenna connected so its not around the key?? I don't remember this from the donor ill have to search pics to see exactly what is there.. I don't have a fuel pressure gauge I should install one as I have a adjustable regulator

Without that antenna, it won't start. It looks like it's part of the actual lock cylinder. It should have a very small two pin (I think) connector that goes to it.

[Samiam1017]

ok I found that its hooked up still nothing I pulled the plug and grounded off the block and no spark.. I do have power,ground,and signal at each coil. I'm gonna go buy four new plugs and try that but these where new

[Bob_n_Cincy]

ok I found that its hooked up still nothing I pulled the plug and grounded off the block and no spark.. I do have power,ground,and signal at each coil. I'm gonna go buy four new plugs and try that but these where new

If you have power, ground ,and signal at each coil and no spark.
Is it possible you don't have a good ground on the engine block?
Bob

[TouchStone]

Do you hear the fuel pump kick on when you turn the key to on?

[Buzz Skyline]

You have spark and fuel flowing to the cylinder? The only way I know of that you can have those two things without ignition is if the engine is totally flooded. So that means you're getting fuel and nearly no air, I guess. Is your throttle working? If you disconnect the intercooler connection to the throttle body, you should be able to check that the butterfly vale is moving when someone steps on the gas pedal.

[Buzz Skyline]

The knock sensor CEL sounds troubling. Could it be that your timing is so far off that it's firing at the completely wrong part of the cycle? Did anyone do anything to the timing belt when the engine was out of the car? (For that matter, did you ever see the engine run before you put it in the car?)

[Samiam1017]

its a brand new factory 257 shortblock with rebuilt 2.5l wrx heads everything is new water,oil pumps and a gates racing timeing kit. so no this motor never ran before. I checked the timing its good. still have to try to swap out some of the sensors.

[Ironhydroxide]

Do you have the fuel going to the correct side of the pressure regulator?

[Buzz Skyline]

How did you check for fuel and spark?

[STiPWRD]

I'm having almost the exact same issue - the engine cranks but won't start. It's a brand new EJ257 with wrx 2.0 heads. I've got fuel pressure, oil pressure, and coil packs are all grounded. I spent the whole day yesterday troubleshooting and had a few CELs. I think if you follow the CELs that will solve your issue. The coolant temp one is the most likely culprit as it may prevent the engine from starting. I had the following CELs: TPS sensor, MAP sensor, Engine coolant temp which are all on the same ground circuit back near the ECU. I traced the harness to a bad connection at the SMJ connector and that fixed the MAP CEL. Next I removed the TPS and it appears to be toast, so ordered a new one. Still working on the coolant temp CEL but it appears the sensor is not getting any power and the ground pin on the coolant connector has a slightly elevated resistance to ground (6 ohms, not sure if that's an issue) but the coolant sensor itself appears to be fine. It is just a huge pain to get too under the manifold.

Long story short, check the sensors and wiring related to the CELs.

[Samiam1017]

I couldn't work on it today I will hopefully have time tomorrow night.. its basically a 07 motor so it has single avcs if a cam sensor was bad would this possible cause a timing issue that wouldn't allow it to start???

[Samiam1017]

I'm going thru the engine harness one wire at a time. I believe the problem is in my dieted harness. does anybody have the diagnostic ecu pages out of the 07 FSM they can email me? [email protected] thx

[904svo]

Is your security light flashing with the key off? It should go off when the key is turn on, if it still flashing you have a security problem with the immobilizer circuit.

[Samiam1017]

I got an email about 5 min after posted the need for diagnostic pages thx Larry (don't know his screen name) I found a few things that need to be addressed before I can try to start again. security light flashes and goes off after I start cranking. I hopefully will get to get the few things straightened out today and will post results. thx everybody for all the hope

[Hindsight]

Where is the security light located anyway? I'm dieting my harness right now and trying to figure out how much of this stuff I need to keep.

[Samiam1017]

across the bottom of the cluster its the 4th light
battery abs airbag security security is directly below the ZA from the impreza printing a inch or so above

[Hindsight]

Thanks, that should help if I run into the issue. Did you leave the keyless entry module and the "body integrated controller" module in place? From what I've read, it seems like you might be able to delete both of these so long as you keep the immobilizer module in place, but I wasn't planning on risking it; was going to leave them in but not connected to any of the door sensors and see what happens. I'm hoping the door sensors and power locks aren't needed (or can at least be shorted to ground or whatever is required to get them to send the right signal).

[Samiam1017]

I removed only the things that I was 100% positive I can remove. so they are still in place I use the key fob to de arm the security system so the security light goes out. i haven't messed with the door sensors they don't seem to effect the security??? I made the changes to my engine harness that I thought were bad and know my DBW throttle no longer works....going back in for more.

[Hindsight]

Hmmm, my donor didn't come with a key-fob, but it did come with the correct key. Car battery was dead when I got it but after charging the battery and using the key in the ignition, it started right up. I didn't need to use a key-fob to disarm the security system and it didn't go off when I opened the door.

[freds]

Hmmm, my donor didn't come with a key-fob, but it did come with the correct key. Car battery was dead when I got it but after charging the battery and using the key in the ignition, it started right up. I didn't need to use a key-fob to disarm the security system and it didn't go off when I opened the door.

Apology, if this is repeating what other posts have disclosed.
My engine would not start....Turned out the Imobilizer unit "antenna" was not connected. I had been looking for a typical external antenna....Wrong!
That "antenna" is behind/around the ignition key assembly. Small white connector at the steering column. Connected it to the Imobilizer antenna ....Bingo!
Turns out the key itself has the electronics that the keyhole antenna talks to..(not the fob)..The key, immobilizer unit and ECU all have to be a matching set, otherwise it will not start.

[STiPWRD]

Did you fix the CELs, especially the engine coolant temp one (P0118)? Several websites I've looked at mention a symptom of this code is a no start condition.

[Samiam1017]

I bought a complete harness from a 07 wrx 1st I replaced the engine harness no fuel pump or throttle pedal. then I tried the rest main harness unmolested same thing???
next I think I may try a new throttle position sensor. would the tps cause a no pump and throttle pedal situation? anybody have any thoughts??? next step is standalone

[Hindsight]

It could cause that. As Chad mentioned once, if you floor the pedal while cranking the engine, it won't fire the injectors. So I'm sure if there is anything wrong with the pedal or the wiring to it, it won't start. If this is the case though, you will have codes in the ECU that reflect this. Do you have a code scanner (generic or Access Port)?

Are you sure the harness connectors are plugged in properly? There are several connectors that join two wiring harnesses together which can be interchanged and if you get it wrong, it won't start.

[STiPWRD]

If you have a bad TPS (or bad wiring to the TPS) the engine will crank and the fuel pump will run but the engine will not fire. I had this exact problem - my wiring was bad but the TPS was fine.

If you have an engine scanner, you should be able to hook it up and monitor the diagnostics (key at ON position, engine not running). You should be able to press the gas pedal and the TPS should tell you what % you're pressing. If this isn't working, the car won't fire.