505 Turbo - won't exceed 2750-3000 RPM

[trymes]

So, I have taken my first step into Peugeot ownership by purchasing an automatic 505. The car is in good shape, but needed attention to the brakes. I replaced the master cylinder today, and that now seems fine.

However, I have an issue under acceleration. Basically, the car has the following symptoms:

1.) High idle when warm - 1250 RPM

2.) Hard starting when cold: dies unless you rev it up.

3.) once warm, the engine pulls normally, you can hear and feel the turbo start to spook, and then once the engine hits 2,750 RPM, it starts kicking and bucking, perhaps knocking (though the dash indicator does not light (it does when starting the car), and basically running like a bag of...you know. This happens regardless of whether you are at low speed and really give it the boot, or if you gradually increase speed to 65 or so, where the engine is normally at 2,750 RPM. It's much less violent if you have a small throttle opening.

i was wondering if this might be a timing issue? Too much advance as the boost comes in?

Where else should I be looking?

Many thanks,

Tom

[Goce]

Might be ignition of fuel related, you must diagnose it, try changing the spark plugs and inspecting the entire ignition system, wires, rotor, cap, igniter, coil, for the high idle and dies when cold might be an idle valve dirty or bad or just a dirty throttle body, but if is breaking up at boost i'll start at the ignition, sounds like you're blowing away the spark.

[trymes]

Thank you! I forgot to ask: where are the timing marks on this beast?

[Goce]

In the usual place, crank pulley and engine housing.

[SRDT]

Maybe it's overboost injection cutoff, it's strange not to have a knock indicator on the dash ; do you know the version of the engine?

[trymes]

 

1 hour ago, Goce said:

In the usual place, crank pulley and engine housing.

Ah, so I just have to get the strobe around 15 belts and such!

1 hour ago, SRDT said:

Maybe it's overboost injection cutoff, it's strange not to have a knock indicator on the dash ; do you know the version of the engine?

That does sound like what it's doing. Is very gentle if you barely have the throttle open and cruising, while it's very aggressive if you put your foot in it. The engine is a GPE2.1V5FACX from the label on the underside of the hood, I can't find the other code. 

 

Its an '86 Turbo.

[trymes]

Update: I spoke with Brian holm, who was quick to point out that he isn't a gas-turbo specialist, but he gave me a few things to look into. 

I disconnected one of the wires leading to what I believe is that over-boost protection switch, and the car doesn't exhibit the behavior, and it feels like it would go like the hammers of hell if I were dumb enough to put my boot in it (right up until it grenaded).

In addition, the boost gauge will go high when exhibiting the behavior, though it is clearly getting interrupted on its way up.

Any thoughts on how to proceed in troubleshooting?

[SRDT]

Check the free movement of the wastegate and actuator, check for leaks on the actuator hose ; you may even find some kind of aftermarket bleeding valve:

[Goce]

Check the rubber line on the turbocharger, for cracks or splits, then remove it from the turbine housing and try to blow in it with a small bicycle pump, you should not exceed 1 bar of pressure to see the wastegate move, if you hear air leaking the diaphragm in the wastegate is bad, if it is stuck try disconnecting it from the flapper maybe the flapper door is stuck, post some pictures.

[trymes]

Ok, I pulled the intercooler and found the plastic elbow at the Turbo inlet is crushed and causing a vacuum leak. That explains the hard starting and bad idle when cold. Placed a rubber glove over it for a moment and the idle jumped right up.

i presume that the wastegate and flapper can only be seen from under the car?

[trymes]

Should I be able to move the wastegate by hand with the engine off? I shimmied under the car and yanked on it fore and aft and it is not moving.

[trymes]

I'm on my phone, so linking photos is a challenge, but here's two in link form:

https://goo.gl/photos/ygWrvTfYxEA3TDj4A

[trymes]

Photo of the wastegate is now up in the google album, the forum won't let me upload it from my phone.

[Goce]

The spring is very strong on some wastegates i don't think you can move it by hand, in you picture the vacuum line the controls the wastegate is visible, try the pump trick.

[Goce]

As for the crushed pipe, round pipe and a hammer on a stump you can repair it like it never been crushed.

[trymes]

I will see if I can locate a pump to test the wastegate actuator, but I'm not near home. Would the normal failure mode be overboost or underboost?

as for the pipe, unless I'm missing something, I can't really repair it, as it's plastic and cracked/warped. Or are you suggesting that I sleeve it with metal?

[trymes]

And, for those keeping score at home, it looks like the actuator's diaphragm has torn. I hooked a pump up to it and it won't build pressure (I can actually hear the air escaping).

1.) How hard is it to change that part?

2.) Is that part shared with any other vehicle out there, or is it unique to the 505?

[SRDT]

It may be unique, or not. But that doesn't mean you can't adapt another actuator.

[trymes]

SRDT: Agreed, but the other question is whether it can be changed without removing the entire exhaust manifold and turbo to gain access.

[trymes]

Also, my question earlier about whether the part is shared with another car was so I could check with local parts stores. I was pleased to find out today that the distributor cap and rotor are shared with a BMW 320i and a Volkswagen Jetta, so they are readily available here in the USA at nearly any parts store (I got one of each today at O'Reilly's). If that were also true of the actuator (say, if it were shared with a Volvo 740 Turbo, or something like that), then there's a pretty good chance that anyone in a major city in the USA could have the part in hand same-day, or in the worst case,next-day.

[trymes]

So, I had the car up on a lift for something else and I got a better look at the actuator and how it is mounted to the turbo. It looks like one of the bolts is readily accessible, but the second one, if removable, would require three to four socket U-joints and a healthy supply of salty language to get out. If anyone has experience with this, please do chime in.

[Goce]

As memory serves right the 505 uses stock T3 turbocharger which means any of the older vehicles should fit, the way i go about finding parts is, first i remove the defective part from my car and with it in hand i check car junkyard for identical or similar part, if i'm not satisfied with the condition i write down the made and model of the car and go looking for new one for that car.

[SRDT]

Not any, there is more than one T3 exhaust housing:

http://www.505turbo.com/forum/index.php?/topic/3278-n9t-e-ea-garrett-turbo-part-number/

Peugeot only had fully assembled turbos as spare parts so it's not really helpful.

[Bean]

Hi Tom,

If you were replacing with a Peugeot wastegate you *might* be able to replace it in situ, but any wastegate you find for it will be used / or very old nee stock.

If you're keeping the car then I'd pull the turbo and intstall a new wastegate actuator.  While your at it - if there's any play in the turbine then it's easy to rebuild the turbo with an updated 360 degree bearing kit.

Another thing would be to make sure your TPS is set up properly (see tech section for procedure), and your timing is spot on.  (Point light at crank from the battery side - 8 degrees I believe.)

I'd provide better details but I'm posting from phone while camping in the Rockies.

Rabin

[trymes]

Thanks, Rabin. Brian Holm is confirming, but he thinks he still has one rebuilt unit. My current plan is to grab that and install it, along with the front rotors and pads, sway bar bushings, etc. From there I can get a feel for how she runs.

I was thinking that one of the off-the-shelf actuators (like the ones HERE) I see out there ought to be something that could bolt right on, but that sort of thinking is dangerous. Something like the adjustable bracket found here might be workable, too. Most generic actuators seem to have two bolts on the body of the canister, and perhaps drilling out the spot-welds on the Peugeot bracket to remove the actuator and drilling holes would allow mounting of a generic actuator. 

Time will tell, as Brian now has me properly terrified that the head is cracked, the ring-lands of the pistons are shot, and so-on, due to overboost. On the plus side, the car now has me interested in pursuing the V6 car a fellow has in Maine for use as a winter car - I need to have my head examined.