joggling on full throttle :-(

[topsnake]

Hello Vipermaniacs,

revived from the dead ones, here I am again. Hope you guys are fine! Some good news for me and some who are interested:
No fuel in the oil anymore! The EU-PCM working with 2 O2 sensors corrected any wrong injection rate. The car now runs even too lean. Not too rich anymore! The spark plugs are quite white, like if it would burn too hot.
Yes this is a story that never ends, but I have to end it, otherwise I will end my ex-mechanic.

My thought is, that I get leak air from somewhere through a broken gasket. I bought some stuff to fix it, but don't know where to start. Intake manifold gasket was brandnew. It could be, that I hit it somewhere, but I dont believe. I think, the injector gaskets are not 100% okay. Is there any kind of manual, how to switch or dismount / mount an injector? Is there any good procedure to find the spot where the leak air gets in?
I tried with brake cleaner, but it seems to be some smaller hole.

When I get on the gas, the engine jumps a little and on full throttle it sounds like it would discontinue ignition for a part of a second a few times in a row (right and left cylinder bank).
This is not a too dangerous fault, but anyhow very disgusting.

The fact, that the engine only shakes on full throttle and not on lower throttle is confirming the thought of a small leak. Only on high demand and high vacuum, the air gets through somewhere... Could be, doesn't it? That the spark plugs look lean could also confirm the leak air theory...

Also with my hardware store - oil in the engine, what I used to wash it from too fuelfuming substances, I had to drive slow and with low rpm. I didn't kick it over 3000/min since I have my new PCM in it.
Could this maybe be also a point, why it's like that? The fault with the joggling came after 200km or more. This more sounds like a hardware fault, what do you think?

Maybe my theories are all crap. Any help is welcome.

Greets and thanks
Dennis

 

[plumcrazy]

im confused, anyone else understand him ?

 

[dave6666]

What year is your car?

There are several ports to the intake plenums. One goes to the power brakes. Plug it and see how it runs. Remember you will not have power brakes during that time.

Also might be one for the HVAC. A small line going into the cabin. You can plug it with no ill effects.

There's another one that is capped at the front of my '01 GTS manifold. For a manometer I guess. Needs cap there.

Your throttle bodies could be leaking at the shaft or at the gasket.

You MAP sensor could be leaking or maybe cracked.

Check your Idle Air Motor. Could be the gasket or the thing is dirty inside.

 

[dave6666]

im cinfused, anyone else understand him ?

Mein Deutsch ist nur fein vielen Dank.

 

[ViperTony]

Let me down a 12 pack and then I'll come back and try to read it again.

 

[94RT10Ohio]

Even though it is hard to read and I have no idea if it is a GEN I or II I will take the subject and say, TB sync needed.

 

[plumcrazy]

at least its not just me....thanx guys

 

[dave6666]

Even though it is hard to read and I have no idea if it is a GEN I or II I will take the subject and say, TB sync needed.

Wouldn't a sync issue be more noticeable a idle, as opposed to WOT like his problem is?

Now a sync would issue however stumbling cause coming off idle of too.

 

[SYNFULL]

The guy is from Germany. I'm sure he's trying his best

 

[Viper Wizard]

Hi Dennis,

How about checking your fuel presser? If it is low, she runs lean, bogs, hesitates. Connect a fuel gauge [with at least a 3' hose] to your fuel port/valve [intake manifold], tape the gauge to the windshield so you can see it while you drive. See if your loosing presser?

Chuck

 

[DAMN YANKEE]

1. He once had gas in his oil, that is now fixed.
2. He has a new PCM
3. He has two new O2 sensors.
4. What was once running too rich may now be running lean. He isnt too worried though.

He has concerns...

1. He thinks he has an air leak.
2. He had the intake off recently, he believes it went back on perfectly but worries that it might not be sealed perfectly.
3. He bought liquid gasket.
4. He doesnt know where to start to use it.
5. He thinks his injectors may be to blame, that they arent sealed properly.
6. He has tested/inspected it with brake cleaner fluid, but found no leak.
7. The engine runs roughly...
a. Small rpm drop in the low rpm range.
b. At full rpm the engine stalls slightly, interupted ignition he believes.
c. He believes that it is a mechanical issue...not a software (PCM) issue.

He wants know...

1. How to test for an air leak.
2. Where to begin to fix an air leak.
3. How long before a new PCM< breaks in properly.
4. Any other advice.

 

[GR8_ASP]

Seriously doubt an air leak is the cause. If it is lean I would think fuel system. Either injectors (correct size?), fuel pressure as mentioned above or something of that sort. Low fuel pressure could be the result of a fuel pump problem, a restriction in the system, clogged filter, etc).

 

[topsnake]

Thanks so far
I have a 2000 GTS with 99 engine and 2000 EU PCM. Should be the first fuel filter since 35000km. I do not even know where it is located? Behind the driver seat directly after the fuel tank?
What is a HVAC?
What is WOT?
I will check the hoses...

 

[Sweet Ride]

HVAC = Heating, Ventilation, and A/C

WOT = Wide Open Throttle (The way Vipers are meant to be driven.)

Hope this helps.

 

[topsnake]

It does, thanks.
I have no A/C anymore. The ventilator is removed also for the cockpit. No heating.
Greets
Dennis

 

[dave6666]

It does, thanks.
I have no A/C anymore. The ventilator is removed also for the cockpit. No heating.
Greets
Dennis

Did you plug the port on the intake then that works the AC?

 

[topsnake]

I don't know what you mean. I have removed the A/C completely with climatic compressor, cooler, all lines and the ventilator.
I could not drive it on WOT so far, we have snow here...

You must be registered for see images

Not too funny with flats.

Greets
Dennis

 

[Fast Too]

Dennis if you removed the A/C completely and all lines, then to Dave666's question. Did you place a plug on the intake port where the line was that used to go to the A/C?

 

[dave6666]

This photo is from a thread I did on changing the intake gaskets. The manifold is elevated onto blocks of wood.

The vacuum line that goes to the A/C system is to the left of the wood block. It is a black rubber elbow with a black plastic tube from there.

If you have removed the A/C, then that port should be plugged or capped.

You must be registered for see images

 

[topsnake]

Thank you for the explanation. I plugged the ****** with a rubber cap. It must be closed. This may not be the problem...
Where is the line to the interior? Am I dumb?

Greets
Dennis

 

[topsnake]

Oh my goodness - I am dumb!
This line is still active, I have plugged a cap on the ****** at the other side of the engine (next to the left TB).
This line is still like it was. Where does it go? What is it's sense? I will close it with a rubber hose.
I drove 150km right now in the mountains (Swebian alpes). The car runs properly and everything is perfect. But this time it was a little irregular, when the putative ignition time-outs and bangs came. First they seemed to be away and only came at 4000/min and after an hour she started to hesitate at 2000 - 2500/min.
Can this really be the problem? This looks like a small line, but would confirm my thought of the leak air.

Thanks for the advice

 

[dave6666]

That line goes to the dash panel A/C knob that controls the heat and A/C. From there it controls the position of the air gates in the A/C system you said you removed.

It could therefore be sucking air, instead of sucking against a solid diaphragm in a pneumatic/mechanical servo.

 

[topsnake]

Hi Dave,

I closed the ****** and it will not longer get air from this spot. I tried the car again but it's like before. Maybe it's just an illusion because I changed something, but I feel, the car runs stronger than before. My snake now stands up at the front wheels at reving up.
I also have to say... After my trip today for now about 140 miles I have a change...
The hesitation stopped and the timeouts of the exhaust sound (I have sidepipes and hear it well ) are not there anymore. Instead of this I have something that sounds like misfire. On 3000 - 5500 rpm and then under WOT I have very loud bangs that sound not normal. When driving on half throttle, nothing happens. At about 3/4 to full throttle the problem sets in.
Couldn't this also be a valve problem? I don't know what to do else...
We have nobody here that is known with these cars. And the one, who acts like he's the Viper master killed my engine and many other things.
The feeling sets in, that it's not very much fun anymore to drive, looking every half second on oil pressure, check engine light, water temp and meanwhile hear the engine not run well after months of afford and heaps of money.
Definitely not the application, I bought the car for. The purity of the car is nearly gone.

 

[dave6666]

Fuel filter condition? How old?

Fuel pressure? Can you check it?

Plugs and wires? How old?

Injector condition? Crappy - low quality - fuel?

Just a few items that could be suspect.

Popping - or back firing - can be a lean condition. The above list can all be suspect there.

What is the year and model of your Viper again?

About the valves... Unless you have damaged the engine - all cylinders alike - very unlikely that it is a valve problem. I mean, if you cook the valves - all of them - it would affect the engine at all rpms unless the PCM could adapt at lower throttle values. Back to the theory of toasting ALL of the engine, do you suspect something major, like the engine ran hot, low coolant, way lean for a while, or?

 

[topsnake]

Hi Dave,

my toasted engine is completely out! To the car again: I have a 09/2000 GTS with now a completely other 99 engine that ran 25000km. Everything that I kept from my stock engine is the intake manifold, the SVS throttles and the injectors as they were.
Fuel filter is 7 years old and ran 35000km now.
Spark plugs are brandnew.
Wires are 35000km old or less (if the owner before switched them once).
Injectors are stock. Was there a change from 99 to 2000? I don't think so, or?
How can I check the wires?
I can maybe find somebody with a manometer for the fuel pressure.

Greets
Dennis

 

[dave6666]

Fuel pressure is checked with a pressure guage. Likely 60 psi or so.

A manometer is for vacuum.

I think the injectors are the same but I am not the expert. Look here:

mopar parts - home

Plug wires are a little tough to check. Pop the hood with the lights out and look for arcing is one thing you can do though. I see new Mopar wires on ebay for like $30.00 frequently. 35000km is not "fresh" any more I believe for plug wires. Supposed to change them every 15000 miles.

 

[topsnake]

Would it be sensible to buy the 8.5mm ones or sth.? The 'better' / bigger option instead of stock ones? Or is this just moneymaking (what's that not)?

Greets
Dennis

 

[dave6666]

I have Magnecores. They are the best and I paid the most. There is nothing wrong with the Mopar wires if you want to save some cash.

I would certainly try to get fuel pressure measurement on your list too. You need the schrader adapter for the manifold to do that. Word of caution - if you have a weak pump or clogged filter you could have good pressure at idle but it fizzles under load.

 

[topsnake]

This would explain the lean looking spark plugs. I guess, this is the next way to go. Couldn't this be also a PCM problem? It may be brandnew but anyhow...
Where can I find the fuel filter without taking off round plate in the trunk behind the driver seat with the washouts?
How many miles can be dangerous for an engine, when it's running to lean? Could I also have killed something for now?

Thanks a lot
Dennis

 

[dave6666]

You say you have a new PCM. Is it matched to the year of the engine, or car? I spoke with DC Performance about a reflash, and possibly getting a second PCM instead of screwing with mine, and the year does matter a little. Slight differences, but different.

I think the fuel filter can be a real pain. You can access it through a removable panel in the wheel well I think. There is a write up in the Illustrated Upgrades forum about making that easier, but you have to be a VCA member to read those.

Why not join? You seem to be a gear head.

Back to your problem... Was rereading some posts and noticed also where Chuck Tator mentioned testing fuel pressure too. Just as I said, would make that the top of the list. Chuck said use a 3 ft hose and tape the gauge to the windshield. Oh, sorry, that's American for windscreen...

Make sure you use good components to do that with. You would not want to start spraying raw fuel if your crappy gauge hose comes apart. And as has been said, you need to get the car up to speed and under load.

The PCM should protect the engine to a point on a lean condition, but after a while physics will take over and you will be shopping for yet another engine.