Fuel pump diag

2

297plc

Member
Car
05 35
Name
Frank
2005 fx35 intermittent no start. When it will start it runs and drives fine, no CEL's or codes. At first it seemed temp related and the battery was fairly old so I replaced the battery along with swapping the ac amp. Cranks strong but the issue persists.

I'll admit I'd never listened specifically for the fuel pump before this, but right now if I turn the key on (without cranking it) I have a high pitched whine from the rear of the vehicle if standing outside it.

At this point it starts only about %30 of the time. How much fuel pressure should I have? Could it be related to the relay? Am I on the right track?
 
297plc said:
2005 fx35 intermittent no start. When it will start it runs and drives fine, no CEL's or codes. At first it seemed temp related and the battery was fairly old so I replaced the battery along with swapping the ac amp. Cranks strong but the issue persists.

I'll admit I'd never listened specifically for the fuel pump before this, but right now if I turn the key on (without cranking it) I have a high pitched whine from the rear of the vehicle if standing outside it.

At this point it starts only about %30 of the time. How much fuel pressure should I have? Could it be related to the relay? Am I on the right track?
Click to expand...


If you can hear the fuel pump, I would say this is not a fuel issue.
The engine should start and run, may be poorly, even with very low fuel pressure.
Sounds more like an imobilizer issue, since there is no CEL.
 
Thanks for the reply! I hadn't thought of that, one thing is I don't have an i-key and this is a non-nav fx with just the orange screen.. I've got a 3 function fob and an ilco branded remade key. Not really anything to program key wise I didn't think. I don't see any security lights or any codes.. Are you suggesting it's a communication issue with the key?
 
Does the first gen have the port you can stick your key fob in?

I have nothing to really contribute. Right now you have about 50,000 possibilities - hopefully we can get that down to 25,000.
 
No port that I'm aware of and no remote start etc. Im not too sure that my fob isn't generic/aftermarket like the key.

If it is a communication/theft defense issue will it crank but not start or just do nothing when you turn the key? At random? Is the immobilizer even in the equation with non i-key models?

Thanks so much for the help everyone, kinda stumped here and spitballing possibilities!
 
297plc said:
No port that I'm aware of and no remote start etc. Im not too sure that my fob isn't generic/aftermarket like the key.

If it is a communication/theft defense issue will it crank but not start or just do nothing when you turn the key? At random? Is the immobilizer even in the equation with non i-key models?

Thanks so much for the help everyone, kinda stumped here and spitballing possibilities!
Click to expand...

It could be a lot of things...
When you have the NO Start situation - does it crank over?
If it cranks, but doesn't start chances are that the ECU is not getting power due to a faulty ignition barrel - I have seen that many times ( especially on GM vehicles ) when people have huge and heavy key chain collection attached to the ignition key.
I remember working on a Nissan Murrano (same engine) with a no start, no CEL, but crank situation, where it turned out to be the wires to one of the coils with stripped insulation, from the heat, and shorted - so no spark.
That said, you don't have ONE simple answer to that problem - might be a good idea to get it to a garage where they have worked on issues like those and ask them to start with the ignition barrel.
 
Another avenue I haven't explored! And yes, cranks/turns over just wont start. I would expect a shorted coil wire to throw a code but I'll definitely give them a look. I need to check for spark and fuel. From there I'll know which direction to go, and it seems very possible that the ignition tumbler could play a part in it.

I'd rather not have to take it somewhere unless necessary, which might end up being the case. Fortunately it's not the only transportation for the household so not putting me in a bind, but frustrating that I haven't been able to figure it out.

To everyone so far, thanks a million. If anyone has any other ideas feel free to share! I'll be going down the list tonight making sure to be thorough.
 
I've had this scenario twice on my life. Always helps to step back and take a breather.
A gas engine needs 3 things.
1.) Air
2.) Gas
3.) Spark / ignition source.

I imagine you have 1 so you are correct in isolation of 2 and 3.

Do you have a code reader? I have a 20$ obd reader that pairs to my smartphone. BEST car tool i own. It lives in my glovebox.

Anyway do some testing and report your findings. Maybe we can keep stabbing at this thing.

Additional symptoms. Any sputtering or sound like it tries to turn over? Backfires? What was the last action that took place to this vehicle before the no start condition? Anything get screwed with? Battery unplug?
Check the fuses yet?(honestly it makes sense to isolate spark vs fuel first)
 
In continuation of diagnosing this issue I noticed something, when it WILL start the security light on the dash blinks, but every time it WONT start the security light stays on solid.

Is this a communication issue with my key?
 
I have had an issue with the car won't start due to the car was out of gas. I have CEL on though. It triggered some sort of engine immobilizer error. I reset the CEL and car start.

Can you confirm there is gas in the tank? You can reference this DIY to confirm gas level in tank. Just a thought!
Gas Gauge Level Fix
 
It's definitely got fuel, the gauge has never been obviously wrong and I do my best to keep it topped off.

It's seeming like a security issue after noticing the change in the dash light in the no start instances. Is it a transponder communication issue? Do I just need a new key? Has anyone experienced that?
 
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