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Hi Dimos,
An exhaust leak would normally present as a chuffing sound as it is a pressure release, not a sucking sound created from vacuum.
That should be relatively easy to locate, especially if someone were to partially block the tail pipe to build extra exhaust pressure in the system so it becomes more pronounced for you to zero in on.
If you are smelling exhaust fumes (I am assuming when you have the bonnet up and are leaning over the engine), then logically they have to be from the primary side of the exhaust system.......either manifolds, cat converters or Y pipe that brings both cats into the single exhaust pipe. Anything downstream from there and you wouldn't necessarily get much odour coming back under the bonnet. An exhaust leak would not normally make the engine run noticeably poorly, unless it was severe enough to upset the effectiveness of the O2 sensors pre or post the Cat converters.
I would like to clarify with you (as I have become a bit confused with the description of fault).........
The loss of power is only when engine is placed under load, in gear and trying to accelerate?
Otherwise it revs up normally when in neutral, but you hear a heavy vacuum sound as engine revs are falling after you release the throttle?
Is the vacuum sound you hear stronger before or after the throttle body assembly?
FYI....here is a picture of our 2.1 throttle body and the idle bypass solenoid I was referring to previously. You can see it has a socket on it for connection to engine loom.
Did you remove and refit this solenoid when you did your initial throttle body cleaning? If so, is the gasket still good and was it refitted the right way around ( i think it's shape has a right way and wrong way to seal properly).
Today I found out something cool: the manifold bolts were loose!!! I somehow desided to check them, since the moment I leaned on the manifold to look at the hoses and I felt like it was moving...
Two of the bolts cannot be screwed at all, in fact one of them came out just by pulling in out with my fingers
I screwed carefully the rest of them. When I moved the manifold just a little bit, the engine confused so much, it almost stopped working. The air leak was so obvious.
After screwing them everything normalized but then again, there are 2 bolts less in the body.
What should I do now? Is there a way to deal with this new task???
You are suffering from the inserts that they put into the plastic intake. All that I can tell you is to pull the intake off and then work on getting those bolts off. Some people have gotten lucky and by loosening the bolt, they have backed out. Others have had to cut the heads off, remove the intake, then pull out the bolt/insert to then remove the bolt and then buy a new bolt to replace what they had to destroy. ONce you get the intake off, you can try using say some JB Weld or some other similar product and glue the inserts back into the intake After the glue dries, you can make sure that you have the proper clearances and then reinstall everything. Unfortunately, you have about a 5 hour job ahead of you. Pulling the intake, especially if it is your first time, can be a bit of a slow process.
Hi Chris!!!
Let me tell you what I understand:
The plastic part underneath the intake has some kind of plastic ring that holds the screw when we start to screw it; it holds the upper with the lower part of the intake, right? And if I don't get this two parts tighten together, no issues will be solved, right?
But then again, if I do all this, it will be proper to change the intake's gaskets too... The spark plugs is a good thing to do as also.
Am I right?
Dimos, you are on the same train of thought that I tend to provide. If you are that far into the car, take care of all the nagging stuff. The new intake seals are cheap. They are reusable, but if you haven't replaced them in the last 50K miles (or don't know how old they are), this is some good insurance to make sure you don't have to go back in (you will find it isn't hard, but does eat up quite a bit of time). Same thing with the spark plugs. You have all this stuff off, might as well spend a little extra money and time to get those out of the way too (but of note, do not go fancy with the plugs, the multi-spark are not tolerated by the Jaguar engine, stick with a basic double platinum plug).
As for getting the inserts set, you can have one or 2 of them loose, but, the more you have loose, the more likely you are to have issues. This is why I say if you have 2 loose, take the time and save yourself a lot of "lost sleep" worrying about when the car is going to act up again. Fix it as best you can and go from there.
I had a similar issue while removing my intake manifold.......two retaining bolts just spun and would not release.
I realized the brass bushings that were encapsulated in the plastic intermediate manifold spacer had broken their binding.
I decided to apply upward pressure under the offending bolt heads with screw driver tips and continue to rotate them until they gradually released from the spacer assembly.
Once they were free and I could get the manifold off I then could put the brass bushings into the vice to release the trapped manifold bolts.
Once separated I then was able to clean out the knurling on the brass fittings and used a Dremel to add some texture to the inserts and damaged receiving sockets before using a high temperature epoxy to reinsert them.
Yes, setting the correct height is important, some inserts are flush and some are proud.
Mine has been fine since, but a trial by fire induction into x-type intake manifold removal.
I wanna share with you what i think, a concern of mine, about all this this situation i am facing: The first replacement i made was the fuel pump. Today, after all these sensor replacements, battery, hoses, checks etc, i tend to think that maybe the fuel pump had no issues. All the symptoms indicated fuel pump problem but these problems were related -as today shows- with the sensors' chain, complicating somehow the fuel flow and/or combustion and/or air ratio in the engine. I am thinking that MAY BE the new fuel pump is not working properly. There are now also symptoms of bad bypass valve: rough start, needs 2-3 times restart, when hot, the car bahves better...
But the main sense is that the fuel is not enough................. stepping the pedal confuses the car, cannot be feed properly, thats what i am feeling
I am very disappointed and frustrated friends...
I don't know what else can i do.....
Dimos, I would start with pulling the IAC valve off of the intake, spraying it very well with some carb cleaner and if you can, put the ports up and fill up the ports with carb cleaner to let it set for a few minutes to really get into the deep crevices if the IAC. Dump out the cleaner and clean it a bit more. Lets handle this as a few separate issues.
As for the fuel pressure issue. What I want you to do is to walk out to the car (off) and press and hold the TRIP button. While the TRIP button is depressed, rotate the key to the RUN position (DO NOT start the car). After a few seconds, you should see the info center say "ENGINEERING TEST". When you see this, release the TRIP button. At this point, you will need to press the TRIP button until you see the fuel pressure (if I remember right, the message center will say "FP1 XX.X" where XX.X is the psig reading of the fuel pressure). You should see something in the 50-60 psig range. If you see it at something lower than 50 psig, then we have an issue. Your year car, you should also have a schrader valve on the intake fuel rail that if you want a mechanical gauge to read the fuel pressure, you should be able to connect one up. If you start the car and again put the instrument cluster in the TEST mode, you should see the fuel pressure in the 40-50 psig range (should be about 55 psig above the intake pressure). If you rev the engine some, you should see the pressure rise slightly (closer to 55 psig) and then drop back to around 45 psig.
Lets see what we have with this and then we can go from there. As a side note, if you depress the gas pedal as you are starting the car and you depress it too much, it will actually cut off all fuel as the car thinks you have flooded the car (think old time carb cars) and that you want it to just cycle air through the engine. So, that may be some of what you are seeing. You do have to depress the gas pedal a lot (essentially floored), but not sure exactly how much it takes to make the system come into effect.
Hi Dimos,
You could be right......it could be a fuel pressure issue.
The fuel pumps fitted in the 2.1 V6 models are 'dumb' devices, just told to switch on through a powered relay.
The fuel delivery pressure is set by the internal relief valve incorporated in the in-tank fuel pump assembly, whereas in the 2.5 and 3.0 V6 cars the fuel pump is managed by the ECM receiving fuel pressure readings from the pressure sensor on the fuel rail, and instructing the fuel pump controller module to regulate the fuel pump speed to govern the output pressure.
Hard start could be poor fuel pressure, or air being drawn back onto the fuel line when car is sitting for any period of time due to air seeping into fuel rail from an injector o-ring, but I would expect you would also be observing a fuel leak if that were the case.
Poor accelerator response coming up off idle again could be poor fuel pressure to injectors or vacuum air leaks in manifold.
If you have no means of measuring the fuel rail pressure, but still have your original fuel pump in the garage, you might consider refitting that to see if your suspicions are justified.
It would be unlikely the idle bypass solenoid is faulty, they get very dirty over time like the throttle body, so you do want to check it is clean and that you can manually operate the plunger and it spring returns itself. If it is not binding and you can manually operate it, your last bench test of the solenoid before you refit it would be to put about 4.5 to 6 volts DC across its connection pins to see that it responds appropriately to an applied voltage. If so, then it should be good to go.
I notice on my car that I get a bit of detectable 'surging' on prolonged deceleration as the engine RPMs decline below 1600 if I am coasting up to a intersection. That minor surging suddenly smooths out just as I pull up, so I think that is an effect of the idle bypass solenoid operating and somehow pulsing a bit.
Just a few minutes ago i conducted this Test mode Chris appointed.
Sadly, as i was very upset with the hard -very hard- start, I don't recall the presure range in the screen and i will come back with the number in my next post.
What i do remember is that the voltage was very low, 12.3 and that is something it shouldn't happen, since the battery is brand new and the road distance to work is almost 5km, long enough to recharge the battery. I think there is -and- an alternator or a cable issue, something i didn't checked as detailed i had to, as shown...
Secondly, about this hard start: when i turned the key to stand by position, i didnt hear this bzzzzz sound i hear, when the system activates the fuel pump. I then realised that this sound does not happen everytime i turn the key; sometimes its heard, sometimes its not. It is like sometimes the fuel pump is not getting some command, i guess
Tonight i got the impression that the fuel path was empty and the fight of cranking was to get fuel to the engine. When this happened, the car started. I don't see any fuel leaks, i don' smell any fuel - as a possible side effect of not sealing properly the fuel pump when replaced. I see no cracks in the fuel cap as also, it looks ok...
Mark, i don't understand which is theidle bypass solenoid you are telling me to clean, please be picture-specific if possible!!
Finally, i see two main options:
replace the alternator cables first, before check for alternator issue and
replace the fuel pump with the old one, as it is obvious the there was no fuel pump issue after all
Place your bets please
Thank you very much, both of you...................................
Chris,
i have already cleaned up the IAC valve, excactly as you say, i will do it again if you think it could helpa. I also have tested this valve in the fuel rail -not today- and it sprayed the hell out of fuel....
Regarding the idle bypass solenoid....See post #41 in this thread....the image I put up in that posting has the idle bypass solenoid circled in green.
It is attached to the upper portion of the throttle body and secured with two bolts.
Just check the assembly internally is clean, the plunger can be moved manually and the rubber seal is not damaged.
I doubt this is the problem, but check it anyway if you are eliminating manifold leaks and other issues that can effect off-idle performance.
Dimos, if you have cleaned the IAC, then that is good enough. Even if that is slightly dirty, it will work just fine.
Now, for your fuel pump, this is where I would say if you have a schrader valve, that would be the ultimate test if you ask me. If the fuel pump is "dumb" and simply runs or not, I think you may be on to something with not hearing the pump run when you turn the switch to the RUN position. It could be possible that you have either a bad pump or the ignition switch is not supplying power. I would need to look at the diagrams to make sure how the pump is getting power and what the potential issues could be. A check that I would try is if you are used to turning the key and hearing the pump, then I would try turning the key a few times and one of times when the pump cannot be heard, grabbing the key and moving it around a little bit to see if the pump starts and stops. That would then point to a bad ignition switch. But, i want to check the electrical diagrams to make sure what I am thinking it is wired like is what it actually is wired like. I don't want to send you down a wild goose chase for no reason.
Hi Dimos,
Sorry for late reply...work got a bit too busy to look up the info regarding fuel pump supply info.
Got home tonight and had to go over to an elderly neighbour to fix her refrigerator....so back on task now for you.
Thermo - FYI, the fuel pump supply voltage is simply switched through relay R7 and the output of that to the pump is protected via fuse F36.
The relay is controlled from the ECM plug EN65-099. That relay control line is fused through F17.
Both of the fuses F17 and F36 and also the relay R7 are located in the passenger junction fuse box.
If the pump is intermittent, then it is possible the relay R7 has bad internal contacts (I had a similar relay issue on mine that controlled the AC clutch that was high resistance and intermittently not pulling the AC clutch in).
Mark please, do not explain, life goes on, thats the way it should be and we have to be grateful for being capable of running around our needs... Hi @Thermo Chris! I have -good i guess- news for you, what did i discover today:
I was into the cables issue today, went to the store and bought two new terminals and cables, decided to start with this tomorrow, before the old fuel pump re-replacement.
I counted about 5 minutes of proper function before the car started to fight with its self.
The alternator when is cold gives 14.3 and after this 5 minutes dropped to 12.5. And that was strange, so i made some rounds around the block, reached the highest temperature and then switched all electricity apps. The car died, instantly.
But yet the alternator is healthy, so, cables were not transfering the load to the distribution.
Checked very carefully, first in the alternator bolt and i saw it: the radiator hose, excactly above the bolt is leaking!! the cable bolt is corroted and green like an alien's face. Excactly where the leak is, and those five minutes is probably the time needed to expand the hose gap by reaching a certain temperature, within a certain time...
So first thing in the morning, cables replacement!
What kind of tools will i need? I will check here, i am sure there is info around.
R7 would be a good replacement idea if you are suspecting your fuel pump is not always starting or working properly for you.
Relays get old and their internal switch contacts can get pitted or dirty, thus become intermittent and high resistance.
Relays are actually difficult to reliably measure, because they might measure OK with a ohm meter across the contacts, but when there is a power load running through their contacts, that is when the poor contact surfaces will misbehave.
WE DO HAVE NEW CABLES positive and negative, and it seems the alternator has no damage, since there is no rough throttle, no up and down, no "i am dying" when i switch all electric applications, it remains steady at 14.6 to 8
But........... :
Even though i feel i am close to spot what the problem is now, i am tired. And i feel i need your advise now, more than ever:
- I repeated the IAC cleaning and as i understand from the black extract, i hadn't cleaned it at all in my first cleaning attempt.
- The car starts smoothly, very easy, the idlle is perfect. But:
- After almost 2 minutes of driving -from cold start- always start to have breathing (i guess..) problems. As i understand it faces 2 major issues and both of them need to be fixed but i am out of money for now, exhausted by all this car/gate thing. So i need your advise in what it seems to be the first in line to be fixed:
P1647: I know this is a long time need, this sensor needs to be replaced. Is this heated sensor and the 2-minutes appear of the problem related? Is it possible to take that time for the ECM to "understand" the faulty sensor?
INTAKE GASKETS: how possible is a potential air leak-faulty gasket result to appear every time after 2 minutes of engine operation?
The only OBDII fault message i am getting is a P1647 and a P1000, if that is helpful at all.
I can afford for now only the money to fix one of these two issues.
What do you say?
Dimos, 2 minutes is an interesting time. I am willing to bet that your problem completely lies with the P1647 code. For the first 2 minutes or so, the car is in what is referred to as open loop. In short, it is not worrying too much about the O2 sensors and really looking to keep the car idling. Once the car sees that it is near normal temperature, it then goes to a state called "closed loop". This is where it starts looking at the O2 sensor and trying to maintain emissions. Depending on what the sensor is telling the car, this can lead to all sorts of issues. That is where I would start. HOpefully the sensor is easy to reach and won't take all that much time to replace.
If that sensor does not fix things, then what I would propose is to see if you can find some black RTV in your garage (high temp RTV, granted, blue should work too). You can pull the intake and put a thin bead of RTV around the seals of the intake and put it back together. That should seal up any leaks that you are having. Not a great long term fix and will make putting in the new seals a bit more of a hassle later, but it will get you back on the road with minimal negative impacts, especially to your wallet.
Granted, thinking, you may be down to only a single issue. You know the cause of the P1647 and the P1000 is simply saying that it sees another code. It is not pointing to another issue. Hopefully you can get a new sensor for cheap. One bit of caution. Do not go super cheap on this and go after the sensors that don't have the plugs on them. I hear far more horror stories than good ones. Spend the little bit extra and get the one with the plug already attached.
This are things going around me and my car!! A few posts ago i wrote about a leak, right over the alternator's supply cable to the battery. It wasn't the only spot the leak was.. The leaking started from a hose crank not obvious in first sight, right over the oxygen sensor! today, after a close inspection i saw the everything round this place was a mess; changed the hose, i removed sensor and if was rusted like hell and its cables, including the harness, were full of rust-dust.
I cleaned everything as much as i could, sprayed the harnesses with contact spray, left em to dry and replaced everything back. Cleared P1647 and started the car.
Very soon the dtc reappeared BUT the car behaves maybe 70-80% better; it is very clear the the transition to close loop it happens and the sensor is energized, maybe not 100% but it is still running somehow. It has to be changed and i am about to order a new one, ot a cheap one but a Denso, starting from 120$ as i checked.
For now, driving is bearable, and after the RTV sealing and sensor replacing, i think i will close this chapter, hopefully.
Quite an adventure Chris and i am so grateful that i found you and @h2o2steam Mark, willing to mess your virtual hands with grease and sharing so many knowledge with me! So grateful friend... but i am still on the run!!!
I will let you know when the sensor is in place and the rtv gaskets ready.
Till then keep you and your families safe,
Thank you from my heart...
10-28-2021, 09:17 PM
