Typhoon Dies Under Boost or Load

[GEMELLI]

I've been having a couple issues with my truck for a month or so. I only get a couple chances a week to work on it, but I think I have the no start problem worked out, so I decided to start a new thread. The under load cut out condition still persists. I've driven the truck around for a mile or so, with no issue, but as soon as the vacuum goes away (the boost tries to kick in), the truck stumbles and will die, if I don't back off immediately. I've had a constant code 34 since the issues first started, but after replacing yet another vacuum line (including the rubber elbow to the fpr), the truck started, idled, and ran (no load) with no CEL. I tried to get into the boost one time, the truck died, and it threw code 34 again. I haven't cleared the codes yet, but I'll do that this morning.

I've tested the map sensor again, and the fuel pressure regulator, and both check out.

I'm just stumped, and any more suggestions would be very much appreciated!


Here's a video of what the truck is doing. After it sits for a bit, it will restart.

http://static.photobucket.com/playe...obucket.com/albums/o270/spdalit/VIDEO0021.mp4

 

[gobabygo]

Re: Typhoon Dies Under Boost or Load

i had a problem like that the other day. mine was the coil breaking down.i didnt find it till the coil completely went out. ran perfect till i put a load on it.

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

Thank you very much for the advice. I tested the coil (measured the resistance), and it checked out good. Just for fun, I also checked the TPS, it was also good. After those tests, the truck wouldn't start again, so now I'm re checking all the vacuum lines.

 

[gobabygo]

Re: Typhoon Dies Under Boost or Load

haha that sounds just like what mine did. hope you get it figured out.

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

I wish I wasn't laughing with you here, but I know this is something stupid that I'm simply overlooking, but... still. I'll figure it out though. Otherwise I'm stuck driving a Ford.

 

[gobabygo]

Re: Typhoon Dies Under Boost or Load

oh lord thats bad!!! get it fixed before someone sees you in a ford...

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

Lol! Does it at least make a difference if it's a Lightning? Not one of those round nose slow Lightnings either. :roll: Anyone can make one of those go.

 

[Flyin Ryan]

Re: Typhoon Dies Under Boost or Load

Figures the ford would be the reliable one

 

[SY-1193]

Re: Typhoon Dies Under Boost or Load

I've been having a couple issues with my truck for a month or so. I only get a couple chances a week to work on it, but I think I have the no start problem worked out, so I decided to start a new thread. The under load cut out condition still persists. I've driven the truck around for a mile or so, with no issue, but as soon as the vacuum goes away (the boost tries to kick in), the truck stumbles and will die, if I don't back off immediately. I've had a constant code 34 since the issues first started, but after replacing yet another vacuum line (including the rubber elbow to the fpr), the truck started, idled, and ran (no load) with no CEL. I tried to get into the boost one time, the truck died, and it threw code 34 again. I haven't cleared the codes yet, but I'll do that this morning.

I've tested the map sensor again, and the fuel pressure regulator, and both check out.

I'm just stumped, and any more suggestions would be very much appreciated!


Here's a video of what the truck is doing. After it sits for a bit, it will restart.

http://static.photobucket.com/playe...obucket.com/albums/o270/spdalit/VIDEO0021.mp4

Thank you very much for the advice. I tested the coil (measured the resistance), and it checked out good. Just for fun, I also checked the TPS, it was also good. After those tests, the truck wouldn't start again, so now I'm re checking all the vacuum lines.

3 things are needed for an internal combustion engine to run.
FUEL, AIR, SPARK.

You say you tested the SPARK (coil) ...but did you check spark at the plugs also?,
A couple of spark plug wires in the wrong order -Check order at the cap and each spark plug?, Arcing burnt plug wires?, Checked the cap/rotor?

Most likely the AIR is not restricted?

Have you checked your FUEL pressure? ~ you tested the regulator but did you test pressure at idle and driving?

Sounds like a dead or dying fuel pump from your video. And yes, a dying pump will start the truck and idle and drive and give up at higher than idle rpm's. The Code 34 is probably low vacuum as you truck dies from lack of fuel. Check Fuel Pressure at idle and driving!

_________________________________________________
...from the book:
CODE 34: Vacuum sensor or MAP Sensor. This will set when signal voltage from the MAP sensor is too low. Instead the ECM will
substitute a fixed MAP value and use the TPS to control fuel delivery. Replace MAP sensor. ~ you tested this right?

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

Figures the ford would be the reliable one

Well, the Lightning did let me down once. Actually, I let it down, but the carnage was the same regardless.

3 things are needed for an internal combustion engine to run.
FUEL, AIR, SPARK.

You say you tested the SPARK (coil) ...but did you check spark at the plugs also?,
A couple of spark plug wires in the wrong order -Check order at the cap and each spark plug?, Arcing burnt plug wires?, Checked the cap/rotor?

Most likely the AIR is not restricted?

Have you checked your FUEL pressure? ~ you tested the regulator but did you test pressure at idle and driving?

Sounds like a dead or dying fuel pump from your video. And yes, a dying pump will start the truck and idle and drive and give up at higher than idle rpm's. The Code 34 is probably low vacuum as you truck dies from lack of fuel. Check Fuel Pressure at idle and driving!

_________________________________________________
...from the book:
CODE 34: Vacuum sensor or MAP Sensor. This will set when signal voltage from the MAP sensor is too low. Instead the ECM will
substitute a fixed MAP value and use the TPS to control fuel delivery. Replace MAP sensor. ~ you tested this right?

I tested the spark at the coil only. I just replaced the cap, rotor and plugs (UR5s, gapped at .028), but I haven't replaced the wires yet. I have double checked the firing order, but I will double check it again.

I was thinking that maybe the cat is getting plugged, but the moisture coming from the tail pipe indicates to me that the cat is working properly. The intake is stock, but free of obstructions.

I did check the fuel pressure at the rail while the truck was idling, and above idle, but not when the truck was under any load. I will check that today.

I have cleared the code several times, and each time it comes back immediately upon start up. It is my understanding that code 34 is low voltage/high vacuum, but perhaps the truck dying is still causing the code. The map sensor tested good, but I did replace it anyway. There was no change whatsoever, so I put the original one back in. No sense in replacing a sensor that is functioning properly.

 

[Damian]

Re: Typhoon Dies Under Boost or Load

I'd say the fuel pump. My GTO did the same thing, ran fine, idled fine. As soon as I tried to punch it, it couldn't handle it. Took it in and the fuel pump was bad.

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

That makes sense. As soon as I get off work, I'll check the fuel pump. I'll use the search too, but while this thread is active... What should the fuel pressure be at idle, off idle, under load? What will determine if the fuel pump is bad? The stock fpr ups the fuel pressure 1 psi per pound of boost, is that correct?

 

[QWERTYphoon]

Re: Typhoon Dies Under Boost or Load

My guess is either the fuel pump or the injectors. Measure resistence in the injectors?

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

I just checked the fuel pressure at idle, off idle, and under as much load as I could give it until it died. I wasn't able to drive it because I had to get the pressure at the rail. Here's a video of the results.

I am checking the injector resistance now, on as many as I can readily get to. Does anyone know what the resistance should be on them?

http://static.photobucket.com/playe...obucket.com/albums/o270/spdalit/VIDEO0027.mp4

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

It looks like the injector resistance should be ~14.5 ohms. I'm checking now.

 

[Damian]

Re: Typhoon Dies Under Boost or Load

I can't see the video but I'd say with great confidence it's the fuel pump.

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

Obviously, the injectors for cylinders 1, 3, and 5 are much easier to get to, so those are the only ones I checked. Their resistance was 15.2, 15.0, and 15.1 respectively. I will check the others, but I just don't have time today.

I'm not sure why you couldn't see the video, but I have a feeling it will confirm what you're telling me.

Here's a different link to it.

http://s122.photobucket.com/albums/o270/spdalit/?action=view&current=VIDEO0027.mp4

 

[Damian]

Re: Typhoon Dies Under Boost or Load

It's not your fuel pump, I was expecting to see the pressure drop off big time but it didn't. Do you have a wideband O2 sensor by any chance?

 

[neildemo]

Re: Typhoon Dies Under Boost or Load

You try a Different ECM? Possibly overboosting and the ECM shutting down. just Vac lines leading from your boost solenoid to Wastgate securely connect? no Holes or rotting. When Your driving it does the boost get pegged? before shutdown? T

 

[GEMELLI]

Re: Typhoon Dies Under Boost or Load

I didn't think it was the fuel pump, but I'm not even going to pretend I'm a SyTy expert. With that said, the only thing I can think of now is a vacuum leak. I've checked all the lines, based off the emissions sticker on the core support, but I feel like I must be missing something. Maybe it's time to replace all the vacuum lines.

I don't have a wide band installed yet. I've been really good about leaving the Ty stock, but I'm learning so much, that the mod bug is getting to me. I'd have say, based off of the smell, it's running pretty rich though.