Rep Power: 0

I have a 2006 Civic LX Coupe, manual transmission, that will crank all day but won't start. The engine shut off while I was accelerating on the highway, and it has only cranked since. The check engine light is not on, and my Foxwell scanner does not detect any codes. Now let me preface this by saying I'm a novice when it comes to cars, but I think I've narrowed the problem down a bit.

SHORT VERSION
My ECU will not pulse the injectors, so the engine is not receiving any fuel. This seems to be a decision the ECU is making, meaning either the ECU is bad or something is telling it not to pulse the injectors, while at the same time not producing a code for some reason.

Here is what I've concluded is NOT the problem:
- immobilzer
- anything fuel-related up to and including the fuel injectors
- main relay
- PGM-FI relay
- fuel injector wiring
- battery
- crankshaft position sensor
- camshaft position sensor
- MAF sensor
- I sent my ECU to G7 Computers to be fixed, but my problem persists

**I'm still a novice, but I've been down a very long path of diagnosing to get to this conclusion. I'll list my lengthy and frustrating experience in a reply to this post, please read that if you'd like to verify the accuracy of my conclusion**

QUESTION
I'm thinking my timing belt may have skipped a tooth, but would I be able to crank consistently if that were the problem, or would my injectors still pulse at some point? Is jumped timing my problem? I want to be sure before I look into it further, as I'm a bit intimidated about taking my engine apart. I've cranked and cranked and the rhythm has never changed, my injectors never pulsing. The only other thing I can think of is that my computer is still the problem and G7 didn't fix it, but I'd like to give them the benefit of the doubt. They said there was no hardware issue so they didn't open it up, but there was a software issue that they fixed. Could my computer still be the issue? Have I been bamboozled?

 
Rep Power: 0

PARTS REPLACED
In an effort to nickel and dime myself to death, I've replaced the following parts while chasing Google suggestions:
- spark plugs
- crankshaft position sensor
- camshaft position sensor
- mass air flow sensor
- main relay
- PGM-FI relay
- battery

DIAGNOSIS (SENSORS)
- 2 different code readers do not detect any codes.
- investigated possible immobilizer issue. Green key light does not stay on. Remote locking still works fine.
- cranking with crankshaft, camshaft, or MAF sensor unplugged will produce CEL light and codes, but no change in crank/no start.

DIAGNOSIS (FUEL)
- car tries to start while spraying starter fluid into air intake, but never actually does.
- fuel pump can be hear priming every time car is switched on.
- unplugged fuel line from fuel rail. Fuel sprays out every time car cranks.
- connected fuel pressure gauge at fuel rail, reads about 58 psi while cranking.
- took fuel rail out of engine and pointed outwards while still connected to fuel line, so as to see if injectors sprayed at all when cranking. They do not spray.

DIAGNOSIS (FUEL INJECTORS)
- attached noid light to each fuel injector connector. No light while car is on or while cranking.
- while injector was attached to fuel rail but not to electrical connector, touched 12V to injector prongs. Injector sprayed fuel.
- tested 12V wires on injector connectors. Each injector is provided with 12V when car is on.
- found ECU pinout and located 4 injector signal wire pins. All 4 wires show continuity from injectors to ECU connector.

DIAGNOSIS (ELECTRICAL)
- bought a charger to recharge my battery every time I crank it to death, which has happened a few times now.
- tried to jumpstart, no change.
- left battery and ECU unplugged overnight several times, no change.
- tested and cleaned several ground points, specifically G1, G2, G3, and G101.
- tried to start car with jumper cable attaching engine directly to negative battery terminal. No change.
- tried to start car with several grounds directly attached to negative battery terminal. No change.
- tried to start car with scanner plugged in, no change.
- took spark plugs out while still connected to ignition coils. While someone else cranked the engine, I touched each spark plug to metal and looked for spark. Each plug showed spark while cranking.

WEIRD THINGS
- tachometer will jump up and down intermittently if I crank long enough
- **Car has randomly started exactly once before quitting again.**
One day, when I went to start my diagnostic session, I had the battery out, ECU out, and fuel rail pointed outwards so I could see if the injectors sprayed while cranking. I started many diagnostic sessions like this. But this time, when I hooked up the battery and ECU, I noticed my injectors actually sprayed. I connected the fuel rail back in place and my engine started on the first crank. Almost immediately (and stupidly) I gave it a little bit of gas (it was still in neutral), and the engine cut off right away. I hadn’t done anything different, but I tried to replicate the circumstances anyway. I have not been able to get my car to start again. It’s just weird that it started once out of 50 attempts.

 
Rep Power: 0

THE CAR
I bought this car used a few months ago. Guy did his own work on it, everything seemed fine when I got it. About a week later the A/C compressor went out and was rattling under the hood. I eventually got it into Firestone for replacement.

LEAD-UP
There were a few mornings (not cold mornings) where my car had to crank a little longer than usual before it would start. Eventually I replaced the battery, and I think the issue still occurred once more after that, but I don't remember for sure. I didn't think much of it. This was before my A/C compressor was replaced.

FIRST PROBLEM
Maybe a week after I got my A/C fixed, my car wouldn't start after work. But it would crank. A little research directed me towards a possible fuel issue, and though admittedly I barely knew what I was doing, I thought I couldn't hear the fuel pump priming. I removed the fuel pump relay, no change. I jumped the relay (which may have been a bad move), no change. Plugged everything back in, no change, no sound from the fuel pump (I thought), even after I removed my back seats to listen better. So I ordered a new fuel pump assembly from Rockauto.

FIRST "FIX"
New fuel pump comes in, had a bear of a time getting the lock ring back on correctly, but I eventually got everything back in. Still crank/no start. My work buddy comes out and tries spraying starter fluid into the air intake while I crank, and he notices a gas puddle under my car. Turns out I didn't properly plug the fuel line into the new fuel pump. He plugs it in and my car starts right up. Problem solved, right?

SECOND PROBLEM
The same day we got my car running again, I drive about 30 minutes on the highway before my tachometer goes wonky for a moment, and my engine shuts off. I pull over and crank, tachometer goes up and down for a moment, but the car won't start. I stop, wait a minute, crank again, car struggles but starts. I drive for another 15 minutes and get home alright with no further issue.

CURRENT PROBLEM
Leaving home that same night, I drive about 5 minutes to the interstate. Shortly after the on-ramp, I shift to 5th gear and start going about 50mph. Then, right as I give it more gas to accelerate, my engine shuts off almost immediately. I pull over and try to start, but it only cranks and cranks. I tried a couple of things, including using starter fluid while someone else cranks. It will try to start, but never actually does. I eventually had to have it towed to my house, where I've been trying for weeks to get it to work. It cranks consistently, with no change in sound or rhythm. But it will not start.

 
Rep Power: 221

06 is a chain not a belt, you should still check if the engine is in time. Did you use oem sensors or aftermarket? Compression test?

 
Rep Power: 0

Thanks for the reply!

I've gotten all my parts from AutoZone so far, I'm slowly learning that might not have been good enough. I'm on my way to get a compression tester now, but I think the problem may still be my crank sensor.

I was looking at some scanner readings when cranking and found that my FTP sensor was flipping between a reading of 0 kPa and something like -0.865 kPa. I've heard the FTP sensor reading is taken into account for fuel injection, so I went to unplug the sensor to see what it would do. Curiously, no check engine light came on, and the FTP reading stayed solid at 8.something kPa. I plugged the FTP sensor back in and cranked, and suddenly I got a code P0335. I hadn't messed with the crankshaft position sensor since I replaced it.

​​​​​​Now I'm thinking maybe I just needed to order a Denso crank sensor all along and everything else was a red herring. I'm gonna see if I can track one down and do a compression test just to verify that it's in spec.

 
Rep Power: 366

car-part.com for nearby scrapyard to get some OEM sensors

 
Rep Power: 0

Thanks for the advice!

I went to a nearby scrapyard and pulled both the crankshaft and camshaft sensors off two different 2008 Civics, the closest I could get to my car. Since it's the same gen and they both looked identical to my car underneath the hood, I'm guessing it's alright? I also pulled the entire charcoal canister assembly (just in case), since it was quicker than only pulling the FTP sensor and somehow just as cheap. This scrapyard has a 90 day return policy too, I'll probably start going here for parts first from now on.

I put the first pair of sensors in my car and cleared the P0335 code, but no change. Still crank/no start. I have not, however, gotten the code to reappear. I had to put my battery on the charger again, but after it's juiced up again I'll try the other pair of sensors.

 
Rep Power: 0

I went ahead and did a compression test after I installed a crankshaft and a camshaft sensor from the scrapyard. I looked up a video on how to do the test, but since I've never done it before, I'll list my steps here in case I did something wrong.

I removed all four of my ignition coils and spark plugs, as well as the fuel pump fuse under the dash. Then I repeated the following process for each cylinder: I screwed in the compression guage from Autozone by hand until it was snug in the cylinder, I fully depressed the gas pedal, and I cranked for about 5 seconds 5 times. I then looked at the gauge, marked the reading, released the pressure from the guage, and moved on to the next cylinder. Looking at my engine from in front of the car, I went from left to right. In that order, here are the readings I got for each cylinder:
.
Cylinder 1: ~230 psi
Cylinder 2: ~218 psi
Cylinder 3: ~202 psi
Cylinder 4: ~212 psi

It's worth noting that my battery started to die when I was cranking for Cylinder 3, and I pretty much killed it cranking for Cylinder 4. I don't know if that would affect the readings or not. Are these numbers good or bad? Does this confirm whether or not my timing chain has skipped a tooth?

I'll run the compression test again once my battery is charged. Aside from that, my next step is to try the other set of cam/crank sensors I got from the scrapyard. I should also note that since I put in the first scrapyard sensor pair, my tachometer has not yet fluctuated during cranking like it sometimes did before, and I have not gotten code P0335 like I did earlier today.

I'm also going to switch out the FTP sensor. My Foxwell scanner still shows that my FTP sensor reading just hops back and forth between 0 kPa and -0.065 kPa whether I'm cranking or not (cranking doesn't affect the reading). If I unplug the FTP sensor, the scanner reading stays at 8.268 kPa, and I now get code P0453. Are these readings normal?

I'm open to any and all suggestions and advice.

 
Rep Power: 0

Did you ever figure this out I’m having a similar issue