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Cooling fan, over-revving on idle and HICAS warning light

Posted

Hi guys - hope everyone is well. I have (finally) got the Z back after it having been with the mechanic for more than six months, largely for a braking system overhaul (master cylinder and discs) as well as a few other bits and pieces, but nothing engine related. Engine was good as gold.

 

It arrived back with a cracked spoiler, 141 extra miles on the clock since the MOT on June 11th, a flat battery, a door panel hanging off where he'd fitted (badly) a Halfords fog light, oil cap tightened so far we had to undo it with mole grips, and absolutely no fuel whatsoever, which was just a little more than disappointing :( Furthermore, he just dumped the car outside my gate with keys on the drivers side front wheel without talking to me about his work as I'd asked.

 

However, on firing it up, we find that it is idling while still warm at 1400 Rpm when it should sit around 800, the cooling fan is running constantly and the HICAS warning light is on. We started it up, realised it was over-revving, so just drove it up the drive and parked it immediately. I'm not sure what the issue might be. Any ideas please?

 

I should add that the car has been standing (apart from the miles the mechanic did and a couple hundred more) for around 18 months while I was waiting to get it sorted. My partner thinks it may have put itself into some kind of limp mode?

 

PS. Is it legal for a mechanic on trade plates to drive your car for 141 miles? Might this have been necessary to test the braking system? I haven't been able to bring myself to discuss it with him yet. I really hope this isn't a sign of some damage which has been caused to the engine.

 

Thanks in advance for your help and advice.

Edited by SalliC
Update

Featured Replies

Sorry to hear that mate - sounds like he's either out of his depth or pulling a fast one. Whilst trade plates do permit those in the trade to drive any vehicle, I'd say that 141 miles is beyond reasonable for a customer's car.

 

I am also confused at the comment "a door panel hanging off where he'd fitted (badly) a Halfords fog light" Why would fitting a fog light interfere with a door panel? Surely the wiring would be from the boot, under the carpet, to the dash switch...??

 

Mid-Wales is not too far from Bristol; so if I were you, I'd get your Zed down to Jimmer. Your Zed is in safe hands with the master....:clover:

I have something to say............ It's better to burn out than to fade away..... :tt2:

Hi guys - hope everyone is well. I have (finally) got the Z back after it having been with the mechanic for more than six months, largely for a braking system overhaul (master cylinder and discs) as well as a few other bits and pieces, but nothing engine related. Engine was good as gold.

 

It arrived back with a cracked spoiler, 141 extra miles on the clock since the MOT on June 11th, a flat battery, a door panel hanging off where he'd fitted (badly) a Halfords fog light, oil cap tightened so far we had to undo it with mole grips, and absolutely no fuel whatsoever, which was just a little more than disappointing :( Furthermore, he just dumped the car outside my gate with keys on the drivers side front wheel without talking to me about his work as I'd asked.

 

However, on firing it up, we find that it is idling while still warm at 1400 Rpm when it should sit around 800, the cooling fan is running constantly and the HICAS warning light is on. We started it up, realised it was over-revving, so just drove it up the drive and parked it immediately. I'm not sure what the issue might be. Any ideas please?

 

I should add that the car has been standing (apart from the miles the mechanic did and a couple hundred more) for around 18 months while I was waiting to get it sorted. My partner thinks it may have put itself into some kind of limp mode?

 

PS. Is it legal for a mechanic on trade plates to drive your car for 141 miles? Might this have been necessary to test the braking system? I haven't been able to bring myself to discuss it with him yet. I really hope this isn't a sign of some damage which has been caused to the engine.

 

Thanks in advance for your help and advice.

 

Christ almighty I hope it's not our old con man lee bent ??

If it is all your good bits will be swapped out bud with Micky mouse parts,if it Isn't him do not ever take it within a 100 miles of him,only use powerzed and you will never look back

 

Ps he used my car for months to do the chippy runs...can you belive that !!

Edited by gray

  • Author

Hi guys. Thanks for taking the time to read and respond.

 

Gaz 300, the brake fluid is fine. I have had an issue with the HICAS light coming on briefly in the past, and topping up the power steering fluid cured it.

 

Funkysi, the "mechanic" is based near to me in mid Wales. I don't want to give any specific name or place since I might need to take further action . However, he's well respected in the area and has been in business for more than 30 years. He told us he's worked on Zs before and seemed quite knowledgeable on some specifics.

 

RichardS, it was the panel in the back by the seat that was hanging off.

 

Gray, it was not Lee Bent. Have noted your comments on him (the name says it all)! I am beyond annoyed since I had a really good mechanic before I moved. Being a girly with little mechanical knowledge, they seem pretty difficult to come by. I've had the Z for more than 20 years and have always taken good care of it.

 

Could I have some advice please on what might be causing the fan to run, what might be causing the over-idling and HICAS light to be on, and, most importantly, would you think the car is safe to drive?

 

Thank you for your time.

Have we found Lee Bents Welsh cousin? Really did sound like him right up to the point about trade plates, lee is not that professional he doesn't even have any kind of insurance. Anyway, gona be hard to diagnose anything, if you want it done right get it to Powerzed, Jim is the only guy who knows what hes doing with these cars.

There is an idle control valve at the back of the engine, could be faulty or missadjusted, or could be tps set wrong or faulty, or could be corroded connections

[sIGPIC][/sIGPIC]

Hi as light could be if steering wheel is taken off and put on wrong, but only comes on after driving for a while, or not getting speed signal from speedo, or low fluid

[sIGPIC][/sIGPIC]

  • Author

Thanks guys. Here's an update.

 

My partner has spent an hour and a half under the bonnet and has found a broken vacuum pipe connector. The pipe is routed under the master cylinder and is pretty tight. Clearly this is the cause of the over-idling.

 

master_cylinder.jpg

 

broken_vacuum_pipe6_com.jpg

 

Here it is a bit bent

 

broken_vacuum_pipe.jpg

 

And now straight

 

broken_vacuum_pipe3_com.jpg

 

 

It seems to be a rigid angled connector - either rigid plastic, or metal. How difficult is this job? We think the mechanic has just dumped it back at my gate because he realises he needs to remove the master cylinder again to fix the problem. Or, that repairing this pipe connector is a difficult job, because it looks like it may be bonded/bolted to the block and you can't get to the fixing without removing the master cylinder again?

 

Can anyone tell us how this connection is made, what it is, is it replaceable, where from, etc, etc? At the moment, it's just flopping about, being held by a small piece remaining connected. We can't get in there and my partner doesn't want to remove it in case the mechanic accuses him of breaking it.

 

Thanks as always for help :)

broken_vacuum_pipe4.jpg

broken_vacuum_pipe4_com.jpg

I’d say that’s a coolant pipe for the water pipes that run under the Plenum rather than a vacuum pipe

The only pipe I have seen recently on doing my engine there is the EGR vacuum pipe, turbo water pipe on that side is facing straight up.

I have deleted all those pipes. It is a fiddly job but undoing some bits you can get your hand under the brake unit, if the metal pipe is broken you can take a pipe from the EGR directly, but very fiddly depends on your experience.

2002 Porsche C2 996 3.6 
1991 Nissan 300zx TT Project

1995 Nissan 300zx TT Crashed 🥲

1997 Jaguar XK8 Scraped ☹️

  • Author

That sounds about right Bones28. Can you tell me what the EGR is please? Sorry for my lack of mechanical knowledge.

Exhaust Gas Recirculation valve, it’s part of the emissions control system. It can be deleted but is a bit of a faff of a job

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