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No boost?

XuperXero

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#1
Flashed Pumaspeed Stage 1+ for 98 Octane tune last night. Boy what a rush, the car is just so much more alive! Peak boost according to my TorquePro app was 26 psi and kicks in hard and early!
But I did notice that the idle was a bit erratic. One light it's hovering 1500rpm, the next it's back down to 750rpm, then the next light would be 950, 1000, 1300, for each time I stopped the car. I assumed that the ECU has to relearn to adapt the tune. So I parked my car and left it as is.

This morning on my way to work, the car didn't felt right. But I wasn't going to push it on a cold engine. So after driving about 15km or so, I decided to push it. Peak boost according to TorquePro... 4.4 PSI. WTF HAPPENED? Idles at 1500rpm every time I'm stopped. I suspected a boost leak, got under the car and checked every hose clamps and also felt around each hose for cracks or splits. Nothing, everything's nice a tight. No leak noise. Seems perfectly normal except for the idle.

Reflashed it back to factory tune and boost is now 5 PSI. I also noticed that the manifold throttle position couldn't hit over 45%, I'm pretty sure I could hit 90+% previously. Idle still at 1500rpm.


TL;DR: FLashed ECU stage 1+, works amazing, park car and leave it overnight, didn't work the next morning, flash stock tune, still same problem.

Anybody got ideas? Did I break something? Sensor? Solenoid? TURBO????
 


Sekred

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Hi Xuper,

That's an usual problem you have. I never had any issues with erratic idle speeds when I flashed stage 2 and 2+.
You could try flashing back to original and then disconnect the battery and see what happens.

I would contact Pumaspeed and tell them about the problem. Contact Tony McQuire: sales@pumaspeed.co.uk
I found he responses quickly to emails.

Sekred
 


OP
XuperXero

XuperXero

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Thread Starter #4
Does your flash come with a MPG tune? You may have activated it last night.
Nope, pretty sure a MPG tune won't increase idle to 1500rpm.

Hi Xuper,

That's an usual problem you have. I never had any issues with erratic idle speeds when I flashed stage 2 and 2+.
You could try flashing back to original and then disconnect the battery and see what happens.

I would contact Pumaspeed and tell them about the problem. Contact Tony McQuire: sales@pumaspeed.co.uk
I found he responses quickly to emails.

Sekred
Hi Sekred,

Already flashed to stock tune with same issue. Just tried disconnecting the battery and making sure all capacitors dead and waited 10 mins. Issue persists.


Is it possible that high boost might have broken something? Another coworker says I probably blew my bypass valve. I did see a peak of 30psi once yesterday.
 


Sekred

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30 psi!, did you here the engine pinging?.
If you have blown the bypass valve you would probably see zero boost and considering its close to the firewall you should here it bypassing as the turbo tries to builds boost.
At 5psi which is about actuator spring pressure, it sounds like your boost solenoid is not operating. Your high idle speed sounds related to the ECU too and the reflash.
You have not mention any check engine lights?.
 


OP
XuperXero

XuperXero

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Thread Starter #6
30 psi!, did you here the engine pinging?.
If you have blown the bypass valve you would probably see zero boost and considering its close to the firewall you should here it bypassing as the turbo tries to builds boost.
At 5psi which is about actuator spring pressure, it sounds like your boost solenoid is not operating. Your high idle speed sounds related to the ECU too and the reflash.
You have not mention any check engine lights?.
Only happened once, no pinging. TorquePro didn't see timing retard either.

No bypassing noise, had couple of people with more sensitive ears than mine in the car while driving to listen for leaks, nada.

Where's the boost solenoid, what's it look like and how can I diagnose it?

High idle speed persists on stock tune as well..
 


GAbOS

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#7
Did you get it back starting to limp and then it broke?

Either way, the tuner should at least put it back to what you gave it to them as, yes?
(sorry, i know it's China. customer wrong and all)
 


Sekred

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Boost solenoid is on the turbo, black in colour with 3 hoses, vent hose to intake elbow on turbo, pressure supply from compressor housing and 3rd hose running to the actuator. You probably need to remove the intake tube to have a look all hoses are connected. I think the solenoid self tests when you switch the engine off after its been running. I know I can here a clicking noise when ever I switch my car off from that area, you need to have the bonnet open to hear the noise.
 


OP
XuperXero

XuperXero

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Thread Starter #9
Boost solenoid is on the turbo, black in colour with 3 hoses, vent hose to intake elbow on turbo, pressure supply from compressor housing and 3rd hose running to the actuator. You probably need to remove the intake tube to have a look all hoses are connected. I think the solenoid self tests when you switch the engine off after its been running. I know I can here a clicking noise when ever I switch my car off from that area, you need to have the bonnet open to hear the noise.
I know what you're talking about. I saw it today when I was double checking the inlet and outlet hose for leaks. I even felt around the vacuum hoses on the solenoid to check for cracks and see if they're loose. I'm also familiar with the clicking noise, you can also turn ignition on and off without starting the engine and it does the self test as well.

Aside from clicking, any physical way to tell if it's still working properly or not?
 


Sekred

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"Aside from clicking, any physical way to tell if it's still working properly or not?"

Well you could pull it off, not much to go wrong. Its either opened or closed. to me it sounds like its working ok and the fault is related to the Reflash when the problem started.
Sucking air after the throttle body can cause an increase in idle speed, sucking air after the MAF would more likely cause stalling or the engine would not run at all.
You could check the hose above the TB, it justs clips on. May have pop off.
 


Sourskittle

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#11
[MENTION=1568]wspec[/MENTION] I think has a cheat low mileage turbo for sale if need one at some point. Like $250 I think
 


OP
XuperXero

XuperXero

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Thread Starter #12
Took my car to dealership today in the hopes of their OBD reader reading codes. My VIN and ECU Model # doesn't show up on any of their system. W T F. Then again... Insurance had a hard time giving me a policy because they could not find a Fiesta ST in their system either.

Ended up using Ford Escape 1.6T as a dummy for the reader, got no unusual codes.


Now my question is, say if I did overboost to 30psi. What part is most likely to break from factory? I'm suspecting boost solenoid as advised by Sekred and/or wastegate at the moment. Solenoid not working or wastegate stuck open.
 


Hijinx

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#13
The boost solenoid can *probably* handle 30psi, as mine has seen 29 a few times, Sours has seen 28...anecdotal. Anyway, I believe the wastegate would go before the boost solenoid... So I'd put my money on the wastegate being stuck open... That correlates with the boost/vacuum leak (high idle) and low boost symptoms.

Edit- Pull the vacuum tube off the wastegate, and drive it carefully. If you don't build boost, there's your problem.
 


OP
XuperXero

XuperXero

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Thread Starter #14
The boost solenoid can *probably* handle 30psi, as mine has seen 29 a few times, Sours has seen 28...anecdotal. Anyway, I believe the wastegate would go before the boost solenoid... So I'd put my money on the wastegate being stuck open... That correlates with the boost/vacuum leak (high idle) and low boost symptoms.

Edit- Pull the vacuum tube off the wastegate, and drive it carefully. If you don't build boost, there's your problem.
Thanks Hijinx. I'll give that a shot next time issue persists, but in the meanwhile...

Update: Problem is gone this morning on the way to work. Car acted as if nothing happened in the last two days. WTF. Peak 20 psi like factory. This is about 10-15km of drive from home. (I don't push the car until after driving 10km to warm up everything).

Parked the car, flashed Stage 1 again hoping to recreate the problem. Started her up after the reflash. Go for a run. Max boost 6 psi. *slouch shoulder, head down*. Issue recreated itself.
Kept driving to work, needed to pass a car... WHOA 26 PSI and car lurches forward pushing me into the seat. Problem gone again all the way to work (20km drive), WTF. I'm flabbergasted and this is making my head hurt.

We can safely assume something's obviously in abnormal operation. As if something is sometimes stuck open and sometimes stuck closed. Hijinx seems to have best diagnosis so far.
 


OP
XuperXero

XuperXero

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Thread Starter #16
I have stock wastegates and boost solenoids I'd sell cheap :)
Car's still under warranty, easier to get brand new for free [rockon]

Update: Problem is back. I can hear solenoid clicking when turning engine off so that rules out solenoid. Coworker drove my car yesterday, says he can hear my bypass valve even off the 5psi of boost. That leaves one thing left. The wastegate actuator. Unless anybody else has any suggestions or feedback, I'm open to your comments.
 


Sourskittle

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Well dang, that's a lot better option, lol. I didn't even think about a warranty ( having an intercooler pretty much ditches that in my neck of the woods ).
 


OP
XuperXero

XuperXero

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Thread Starter #18
Update: Problem gone this morning.

Current pattern is: Morning on the way to work, no problem. Night on the way back home, no boost. Car is not driven in between. This is making my head hurt.
 


Sekred

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Update: Problem gone this morning.

Current pattern is: Morning on the way to work, no problem. Night on the way back home, no boost. Car is not driven in between. This is making my head hurt.
Did you contact Pumaspeed?.

You could try emailing Andrew Ward, he is the guy that writes the MAXD tunes.
 


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#20
Update: Problem gone this morning.

Current pattern is: Morning on the way to work, no problem. Night on the way back home, no boost. Car is not driven in between. This is making my head hurt.
Hey XuperXero,

Have you tried contacting Ford China? They'll be in the best position to assist. Their number is +86 (0) 800-810-0740.

Nick
 


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