VN 5L drives like a pig after installing cold air intake. Needs a tune?

[raw]

my checklist which is:

coil
ignition module
hall effect sensor in the dizzy
fuel pressure regulator
fuel pump

OK so I finally got some spare time to start checking things out. First I manually tested the fault codes (used the paperclip trick) and got code 12, so nothing wrong there.

Then I tested fuel pressure with the car idleing in Park was sitting at 270 kPa...was told that was satisfactory so fuel pump and regulator should be working ok too.

That's all I've done so far, and next I'll pull out the dizzy cap and check out the hall sensor, and while I'm there will pull out the coil and test it with a multimeter.

Just gotta find the resistance specs for the coil... Is the stock coil in a VN V8 is a Bosch MEC 718? If so I found the resistance specs here. Can anyone confirm?

 

[HARVZ-6]

Just skimmed through the posts,

Could be a blocked cat converter, my sisters ute did this, didnt want to rev, sluggish as hell.. maxed at about 4000rpm, cat had collapsed,,

easy thing to check just drop the cat out and have a look, if you can see through the honey comb its fine

 

[raw]

I've just remembered something. Two things actually.

1. I am an idiot.

2. when I put the over-the-radiator CAI on there are two screws which hold it down on top of the radiator.
I must have either over-tightened these, or the plastic CAI was too big for my car, because the shroud was being pushed into the fan blades when I went for a drive.
At the time of installation this didn't occur to me (see point 1 above), but when I took it for a drive the temp guage increased a little more than normal.
So I pulled over and popped the bonnet and with the engine still running (and hence the fan too) I could hear it hitting the plastic. So I immediately took it off and put the standard intake back on.

Could that have stuffed my clutch fan? It makes sense as alot of the time I can hear the fan revving furiously.
Also this would explain why my car is always cool because even on hot summer days it won't go above 1/3.
When the car is completely cold the fan is hard to move by hand, but when the car is hot the fan is easily moved by hand and after spinning it continues to spin for a short distance.
Is this normal or should it be the other way around?
I've heard conflicting answers about this.
Anyway, I'm going to take the fan off and go for a quick test drive.
Also, the clutch fan is connected to the water pump right, so maybe that has a problem.

So does it sound like there's a problem with either the clutch fan or water pump?

 

[Not_An_Abba_Fan]

The fan is made of metal, the shroud is plastic. Metal beats plastic every time, just like scissors beat paper.

It doesn't sound like there is anything wrong with the fan.

You haven't put a screw though the wiring loom that goes across the top of the radiator have you?

I would also check the ignition module earth incase it has come loose.

 

[raw]

I have tried everything mentioned in the thread, except for the hall effect sensor which I will do eventually but have been putting it off because I'm not looking forward to taking out the dizzy, replacing the HES, re-adjusting the timing etc.

In the meantime I've thought of a couple of much simpler things I might try

condenser - when i replaced the ignition coil I used the same condenser that was on the old coil. Perhaps I should get a new one as they are cheap and easy to fit ???

Also, i've got a greenfoam tune which i will try as well

NOTE: I've updated my original post so that it's straight to the point and easier to understand.

 

[jdodd]

I've just remembered something. Two things actually.

1. I am an idiot.

2. when I put the over-the-radiator CAI on there are two screws which hold it down on top of the radiator.
I must have either over-tightened these, or the plastic CAI was too big for my car, because the shroud was being pushed into the fan blades when I went for a drive.
At the time of installation this didn't occur to me (see point 1 above), but when I took it for a drive the temp guage increased a little more than normal.
So I pulled over and popped the bonnet and with the engine still running (and hence the fan too) I could hear it hitting the plastic. So I immediately took it off and put the standard intake back on.

Could that have stuffed my clutch fan? It makes sense as alot of the time I can hear the fan revving furiously.
Also this would explain why my car is always cool because even on hot summer days it won't go above 1/3.
When the car is completely cold the fan is hard to move by hand, but when the car is hot the fan is easily moved by hand and after spinning it continues to spin for a short distance.
Is this normal or should it be the other way around?
I've heard conflicting answers about this.
Anyway, I'm going to take the fan off and go for a quick test drive.
Also, the clutch fan is connected to the water pump right, so maybe that has a problem.

So does it sound like there's a problem with either the clutch fan or water pump?

hi my vn v8 was gradually getting sluggish and it got really really bad one night. felt like something was holding it back. so i had a listen and could hear a slight grinding noise from the water pump.
so the next night i took it off to replace it and found it was seized up tight and the bearing had let go and the impeller was hitting the timing cover. after replacing it it went like a 5l should.

 

[4wheelinls1]

How hot did it get? Rough on a hot start and sluggush, how does it crank on start? If it is irregular it may have blown a head gasket.

 

[raw]

The temp gauge didn't go past half-way. Normally it would sit on just 1/6, so when it approached half-way I got suspicious.

On startup I've noticed a big change too. It used to start smoothly and sound 'bubbly', but now its rough and the sound is a bit like a 'grating' or raspy sound

 

[jdodd]

yeah it never really got hot, but that did all happen during winter.

 

[GenReaper]

When the car is completely cold the fan is hard to move by hand, but when the car is hot the fan is easily moved by hand and after spinning it continues to spin for a short distance.
Is this normal or should it be the other way around?
I've heard conflicting answers about this.

Other way around, should freewheel when cold to allow faster warmup.
When hot, bimetal strip makes the fluid coupling get more solid and hard to turn so it pulls air when warm cooling the radiator down.

Take fan belt off and check alternator bearings aint siezed while your there.