Well lately my car has been acting really bad.

It's got a bridgeport idle because of the ******* TPS idle hunt.
The car will idle any where between 1500-1900 RPM's and now it's starting to **** up under boost.

Today on the way to work it would start to buck if I went into heavy boost.

If I ran like 1-3psi it would gradually work in and be fine but if I hit the pedal to get around 5-9psi it would start gargling and bucking. As soon as I would let off it would back fire(80% of the time)

The hesitation/bucking is usually around 3k-4500 rpm.
I have an Rtek so the injectors turn on around 3500 rpm.

I never stay in boost to see long term affects since I'd prefer to keep my engine in one piece.

Also a possible linked item.
On the highway in 5th I could boost around 5psi fine. I think it's past the injector switch. It woudl run pretty good until I let off the pedal even a hair.
The car feels like someone ripped the pedal away. No ease of deceleration. A very abrupt stop of acceleration.

I replaced the TPS a week ago hoping it would remedy the problem. No luck.
I adjusted it down to 1 volt but had to push up a little higher to try and even out the huge TPS idle hunt.

I'm almost thinking maybe my ignition/coils are going out. Maybe fuel injector getting stuck open(they were cleaned a year ago)?

 

Oh yeah,
It kind of feels like the car is now slower(not after today but in general).

That's kind of why I think the ignition may be going. Not enough spark to really keep it up.

But then again maybe I've gotten use to the new psi I'm running(boost controlled to 8psi).

 

What's your AFR doing during all of this?

 

What about your TID , I've seen some of the same crap from a crack in my TID.

 

Hey Corey,

Why dont you pressure check your intake system again? Did you save those pressure caps you made? You might have gotten a boost leak.

Rat

 

I do have a big crack on my TID(at the turbo entrance) but I patched it with tape for now and I will make a home made TID soon.


Well.
Here's part 2.
It's running fine under boost now.

It did this **** last week. I would turn the car off and turn it back on and it's fine.
I'll see what happens on my way home tonight.

The AFR's seems to be stable. Not really sure what the real numbers are but I would guess it's around 12(autometer guage).

I'll try to watch the AFR's if it does it again.

 

Cool , good to hear it's better.

 

well.....

The bucking went away.

But I now have a metallic sound coming from the LIM/Turbo area.

Kind of sound like vibrating sheet metal during idle hunt and decel.

SO either my engine went a a small vacation or my exhaust is coming off
(rattling bolts off) or my turbo is eating the hotside turbine.

 

Do you have the heat shealds on ?

 

hey digitech, whats the up date on the motor? mines having the same exact problem the bucking and the vibrating sheet metal sound. let me know pls.

eric.

 

Well.
The motor hold vacuum fine and idles smooth(when it wants to) and I don't throw any uncommon flames. So I figure the engine is fine.

It still idle hunts but the metal sound has gotten much louder.

I believe the turbo hotside is eating the turbine.

Here is the crack I am talking about.


It is common on FC's. Most people never know they have it.

My turbo was rebuilt 23k ago so shaft play and everything is fine.
I will pull the turbo and see if it's ok or not. I might grind the crack down to prevent the edge coming out and hitting the turbine.

 

do you know wat the metal sound is? mines been giving me that problem for so long, i dont konw what it is. its been bothering me. and hella bogs, you think that crack is causing the huge hesitation? i bought the turbo off of rxmnf7 so i dont know, its a t04b hybrid

eric.

 

Well this is the 3rd hotside I've bought so the crack is common. It's possible you have it as well.

The only way to tell is to pull the turbo and look.

 

Just an update.

My dumbass did not tighten down the hotside good enough last month when I ported the wastegate.

So the bolts worked themselves loose and then pulled the hotside to an angle so the turbine was barely scraping it.

SO this time I tightened the **** out of them.

Luckily the turbine wheel wasn't damaged and the hotside was fine other than a small pea sized scape to clean metal. It also didn't have the huge crack I posted about.

So now I've just got to figure out why I get the loping idle.

 

the bucking a hestation could be bad grounds

 

yeah i have the hesitation also i think its bad grounds but ive got no clue how to fix that! the thread in the archive confuses the hell out of me.

 

haha another i found my metal vibrating too, it was my wastegate flapper, the actuator rod came off so the flapper just kept flapping on decel made hella uglly metal vibrating sound, i dont know if i haev the hesitation still or not cuz havent driven the car yet.

eric.

 

I doubt mine is grounds.

I added one big one to the neg terminal,boost sensor to fender, efi block wire to firewall a few months ago.

I've also tested them on several times just to see if it was that.

Mine is either ECU/Harness related or coil related.