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I have cleaned the PTU connectors, the CAS connectors, the TPS connectors and AFM connector, and i've still got a huge missfire, in fact i've proberbly made it worse. This is now really doing my head in, I am desperate to get this to the midlands meet so someone can get a conZult on my Z.

 

It seems all the connections on the coil packs and injectors are loose due to snapped clips, would this have anything to do with it?

 

The main part of the problem was missfiring and struggling to rev by 5000rpm up to 12+ psi, now it's missing on idle and all the way up the rev range.

 

I now do not know what to do as i'm still learning about the Z. PLEASE HELP!!!!!

 

Thanks to Stu (SMW), John Dixon, Ya5een and Jeff who i have been ringing today to help me out, and sorry MAC for forgetting you haven't got your car near you...........DO'H.

 

Rich:(

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The fact you think it made the car worse points the problem to the wireing. (Pushing the boat out there ;))

 

Or it could be dirty sensors. Have you cleaned the water sensors? Not the connectors but the sensors them selves? Not really likely but worth a shot.

 

Is the car mis-fireing, or would you call it a splutter/stutter?

 

Can you check the timing?

Have you looked at the actual wiring to the injectors? (inside) Do they look green and oxidised? Mine had a terrible miss and backfire and replacing injector connectors cured all. Your snapped clips aren't going to be helping at all. I would certainly look at replacing those asap. I mean, coilpacks and injectors provide the 2 most important things - fuel and spark!

With our cars getting pretty old now the wiring really is an issue, I reckon 9/10 faults are electrical/wiring related rather than a failure of a unit or component. All connectors etc have had 13 years+ or so of getting fookin hot, cooling down, again and again.

mine did that , ran like a packet of shit, engine runnig , wiggle wires revs went up and down, changed injector connectors and wire, runs fine now, got the leads from the states, £12 for three

Look at the state of one of my old one's.....now that isn't going to be doing anyone any favours is it?

 

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It is bound to be the wiring to injectors or coilpacks I would say bud. How old are the plugs btw?

The fact you think it made the car worse points the problem to the wireing. (Pushing the boat out there ;))

 

Or it could be dirty sensors. Have you cleaned the water sensors? Not the connectors but the sensors them selves? Not really likely but worth a shot.

 

Is the car mis-fireing, or would you call it a splutter/stutter?

 

Can you check the timing?

 

Stu, i think i have come to the solution that it is wiring!!! LOL

 

The car is doing both, spluttering and missfiring. I will hopefully be able to get the timing checked.

 

James, the wiring inside the injector wiring was green and dirty, I will be ordering some new wiring ASAP. I will also get some new Coil packs as i think as you say after 13 odd years they will need replacing.

 

I have just put new plugs in (denso iridiums) yesterday!!!!!

 

Cheers all!!

 

Rich :)

Oh and my Coil pack connectors look as yours did!!!

 

Rich:)

Oh and my Coil pack connectors look as yours did!!!

 

Rich:)

 

 

I remember just before I took my car off the road, it was doing a strange misfire, but usually after I floored it. After coming down from 6000rpm of something, when I applied the accelerator lightly, it sounded like the car was on constant misfire all the time. It would go when I applied more accleration or let off. There was a certain position (Depending on the gear and how fast I was driving) with the accelerator where it would cause this misfire. Is yours like this? I never found out what it was, but I was guessing heat soak into the wireing loom or bad connections. After I took the loom off I did notice how bad the connections where. Hence new loom :D

 

Stuart

I remember just before I took my car off the road, it was doing a strange misfire, but usually after I floored it. After coming down from 6000rpm of something, when I applied the accelerator lightly, it sounded like the car was on constant misfire all the time. It would go when I applied more accleration or let off. There was a certain position (Depending on the gear and how fast I was driving) with the accelerator where it would cause this misfire. Is yours like this? I never found out what it was, but I was guessing heat soak into the wireing loom or bad connections. After I took the loom off I did notice how bad the connections where. Hence new loom :D

 

Stuart

No mate, mine is intermittant, if i set my boost to stock, the Z goes all the way up the rev range (but still misses/pop's) it's when i up the boost say to 15psi, it misses/pops/bangs etc really bad and will only rev by 5000rpm. as from today it now seems to be firing on four (i dont know which as it got too cold and i was getting too pissed off) on idle, but when you slightly revved the Z, the missfire wouldn't be as noticable.

 

Oh this is doing my head in, Where would be best to get the problem sorted. :confused:

 

Rich:(

Chunk - you don't fancy giving it a go yourself? I'm guessing it would be tricky to lean over with the leg?? Or go to your nearest auto-electrician. First thing is to get hold of new connectors, I am doing a Courtesy order soon and can get you small stuff like that if that is any help?

What about the plugs dude? Are you confident they are ok. Did you read those links I posted?

Check the left hand connector on the PTU - known loads of these to cause untraceable miss fires. Give it a bit of a push/pull - usually a problem after its been off too.....

The fact you think it made the car worse points the problem to the wireing. (Pushing the boat out there ;))

 

Or it could be dirty sensors. Have you cleaned the water sensors? Not the connectors but the sensors them selves? Not really likely but worth a shot.

 

Is the car mis-fireing, or would you call it a splutter/stutter?

 

Can you check the timing?

 

Stuart, do you know a guy called 'Jack shit' ???? :rofl: ;) :D

Chunk - you don't fancy giving it a go yourself? I'm guessing it would be tricky to lean over with the leg?? Or go to your nearest auto-electrician. First thing is to get hold of new connectors, I am doing a Courtesy order soon and can get you small stuff like that if that is any help?

What about the plugs dude? Are you confident they are ok. Did you read those links I posted?

Hi James,

 

I would do this myself but it would be a PITA with my leg, It took me and a mate 4 hours yesterday to do about 2 hrs work.

 

Could you get the connectors for me, Injector, Coil pack and a new TPS connector (the whole one from the TPS to the plug on the other end) Let me know how much you'll need bud! :bow:

 

The plugs should be OK. I have read most of the links, is there a bit that i have missed thats important. I'll get reading again bud. :)

 

All the best

 

Rich:D

Check the left hand connector on the PTU - known loads of these to cause untraceable miss fires. Give it a bit of a push/pull - usually a problem after its been off too.....

 

Andy,

 

I did have a wiggle around with the L/H connection, it did make a small difference, but then started to miss again!

 

Fancy coming to Leicester for a few days...........LOL :D

 

All the best

 

Rich :D

LOL sounds like thats your problem then ;) Can be a royal PITA to get it to make good contact...

LOL sounds like thats your problem then ;) Can be a royal PITA to get it to make good contact...

Cheers bud, I'll get the pipes off again :rolleyes: and git jiggy with the PTU connections.LOL

 

Ta

 

Rich:D

Nah leave the pipes on - fidly but you can do it - just give it a good shove around :)

OK bud, will do, I'll just calm myself down from yesterdays escapades first. :rofl:

 

Rich

Not done it yet bud, I was hoping a mate would come round to give me a hand, but he couldn't make it. He is round tomorrow though so hopefully i can tell thee more then.

 

The problem is that when we finished the Z yesterday my mate who is considerably smaller thaan me, put the Z in my garage and i cant get in the car (cos of my cast, honset;)) So therefore i couldnt get anything done!!!!

 

All the best

 

Rich:)

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