| Author |
Message |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 75
Reg: 03-2006
|
I have a UZZ30 soarer, supercharged with an MP90. Standard ECU, rising rate fuel regulator. Everything else is stock. When I got 20,000k ago it everything was running sweetly. Over time the car has started to run rougher and rougher, it feels almost like a vibration, as if a wheel is out of balance, but it's there when you're idling, so it's engine based.
The car will misfire occasionally, like once every ten minutes, as if the air con compressor is kicking in and the engine isn't coping in time. It does it with the air con off though.
I have replaced the distributor caps and rotors. The spark plugs are the expensive champions, similar to the iridums (shouldn't require replacing etc, and looked fine when i pulled one out. Couldn't be assed getting them all out just yet).
I haven't looked at much else. Before I start randomly testing bits, are there any suggestions?
How do I test if the injectors are working fine?
Could the idle air control valve be causing this?
The thing that's confusing me is the vibrations are intermittent, some days it will be twice as bad (if not worse) as others, and it has been steadily getting worse over time, so it's not as if something's simply let go.
I hate saying it, because I sound like such an old fart, but I miss working on the Torana... So much simpler.. |
Anish Varsani
DieHard
QLD
V8 UZZ30
Posts: 507
Reg: 07-2005
|
Reset the ECU and see if it works.
Failing that, check for a vacuum leak. |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 76
Reg: 03-2006
|
Tried the ECU reset, and I will admit it is a touch better, but far from fixed.
No vacuum leaks that I can find. |
Peter Nitschke
JunkFilterer
South Australia
GT4.0 V8
Posts: 7807
Reg: 11-2004
|
It may be worth checking this.
http://www.planetsoarer.com/IAC/iac.htm |
Anish Varsani
DieHard
QLD
V8 UZZ30
Posts: 508
Reg: 07-2005
|
Does your hesitate and carry on from a cold start?
If you tap the throttle after starting does this make it go back to normal? |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 78
Reg: 03-2006
|
No, it doesn't go back to normal, it's rough from cold through to hot. If it was just rough running i'd be expecting injectors or ignition, but the occaisional stuttering is confusing me. |
Anish Varsani
DieHard
QLD
V8 UZZ30
Posts: 510
Reg: 07-2005
|
Sounds like a dodgy plug or lead. |
Clayton Webb
TryHard
South Australia
'31 V8
Posts: 482
Reg: 09-2005
|
Anish Varsani wrote on Saturday, May 12, 2007 - 10:43 am:Does your hesitate and carry on from a cold start?
If you tap the throttle after starting does this make it go back to normal?
Thats excatly what mine does mate. Do you know the contributing factors? |
Anish Varsani
DieHard
QLD
V8 UZZ30
Posts: 511
Reg: 07-2005
|
Havn't figured it out yet. I just put up with it because the car still drives well.
Hot starts are not a problem. |
Clayton Webb
TryHard
South Australia
'31 V8
Posts: 483
Reg: 09-2005
|
I've changed my spark plugs, the leads tested out fine and I've tried bypassing the fuel pump ECu and it still does it. I think it could be the actual ECU itself by thinking it's colder than it really is and thus flooding the engine when it tries to start. |
Andrew Ferres
DieHard
WA
'86 Cressida V8, '84 Soarer V8, '90 C-F Celsior V8
Posts: 657
Reg: 07-2005
|
I doubt its flooding, its more likely not getting enough fuel on start up, or even more likely the ecu needs some capacitors replaced.
Mine is the same, purely on some cold starts. |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 79
Reg: 03-2006
|
Started at the top and worked my way down. Three of the coil leads produced open circuits, well two open and one at 998 ohms. One of the plugs doesn't match the other 7 either.
Where's the best place to get leads from? Repco want +$300 for a set, would be nice to get cheaper than that.. |
Andrew Ferres
DieHard
WA
'86 Cressida V8, '84 Soarer V8, '90 C-F Celsior V8
Posts: 659
Reg: 07-2005
|
TopGun/Bosch/Eagle should all be around the $200 mark.
Genuine is about $400. |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 80
Reg: 03-2006
|
Just reading the article by peter scott (http://planetsoarer.com/penski/ThePenskiFile.html) has anyone else found this problem with the cheaper leads, that they're practically crap? |
Andrew Ferres
DieHard
WA
'86 Cressida V8, '84 Soarer V8, '90 C-F Celsior V8
Posts: 660
Reg: 07-2005
|
I've had many problems with aftermarket leads, but only when trying to remove them after they've done a few months service.
They are still fine electrically. |
Peter Nitschke
JunkFilterer
South Australia
GT4.0 V8
Posts: 7864
Reg: 11-2004
|
I have the Eagle leads from Neil, so far no problems. |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 81
Reg: 03-2006
|
FYI:
Genuine Toyota leads: - $462 (inc. GST)
Bosch Leads (from Supercheap) - $240
NGK Leads (from Supercheap) - $295
I'm going to try the Bosch, measure them up and see how they compare to originals. Also a set of new iridium plugs is going in, BKR6RIX-11, no point stuffing around really, seeing how i've got to remove the throttle body to get the drivers side access cover off. |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 82
Reg: 03-2006
|
Bosch leads have arrived (less than 24 hours, that's surprising for Supercheap)
Let's test em. Would be nice if the bastards were numbered. Numbers beside lead do not reflect spark plug number, just order tested.
1 - 6.2 ohms
2 - 3.7 ohms
3 - 3.7 ohms
4 - 5.8 ohms
5 - 5.2 ohms
6 - 5.1 ohms
7 - 1.8 ohms
8 - 1.8 ohms
Coil 1 - 2.3 ohms
Coil 2 - 1.8 ohms
Okay, so not as high as the original items, but there are no broken ones in here, and they could be worse. That and they're half the price of the genuine items. When the new spark plugs arrive will throw it together and tell you how it goes. |
Anish Varsani
DieHard
QLD
V8 UZZ30
Posts: 513
Reg: 07-2005
|
ohms or k-ohms?
Leads are typically in the k-ohms. If they weren't you'd need very high current ignition coil. |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 83
Reg: 03-2006
|
You know what I meant.. |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 84
Reg: 03-2006
|
My... freakin.... gawd...
Changed the leads and plugs, threw in a new air filter, and I am astounded at the power gain. I'm assuming the plugs were a large contributor, seeing as they appeared to be the original plugs, but the leads weren't helping i'm sure. Best $400 i've spent so far. |
Anish Varsani
DieHard
QLD
V8 UZZ30
Posts: 520
Reg: 07-2005
|
Did the leads fit ok?
Can you post up the part number please? I need to change mine out. |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 85
Reg: 03-2006
|
The leads were about 1/4" longer than stock, which works in my favour, as it helps them get around the supercharger. And in reality, on a stock motor they'd be fine, that little extra length just needs to be bent into the right place, which isn't hard.
Part number is B8040i, cost just under $250 from supercheap, well worth it. I reckon i've cut a good second out of the 1/4 mile time. |
Anish Varsani
DieHard
QLD
V8 UZZ30
Posts: 521
Reg: 07-2005
|
Are you running stock heat range plugs or did you go one colder? |
Luke Bartlett
Tinkerer
Queensland
Soarer V8
Posts: 86
Reg: 03-2006
|
Stock heat range (6), as i'm only running 4psi. |
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