Been checking through past posts and have come to the conclusion that my PTU (yes, s1) has failed. I remember seeing on some tech help thing how to open the PTU and check for bad connectors and was wondering can you tell by looking at the inside whether it has definately gone? Below is a description of what happened to my car so you can maybe help me find the problem

 

Driving car. Randomly a water hose came off and engine over heated a tad before i could pull over. re-filled the water and re-attatched hose. Started ok when i tried it first time (30mins after stopping). Engine ran fine for about 10mins then started to lose power and then cut out completely (about 40mph). stopped car and woulnd't re-start. Had to put it on a flatbed to get back from spain. yes spain.

 

Gonna order an s2PTU at the weekend any way but anticipating what else it could be....

 

Cheers in advance as missing my Z.

 

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longest post ever.

Hi bro, ok, well first things first, you need to know why that water hose blew off ?

 

Could be pressure that blew it off which means you have head gasket problems, if it were that bad id expect some steam from the zorst.

 

Did the gauge shoot up on the dash ? the water temp gauge I mean.

 

From my experience when my S1 ptu failed there was no warning just as soon as it got hot bang you lose all power, but it wasnt cutting out with the throttle on, it would cut out when you let revs drop at a junction etc.

 

You cannot open it up feasibly and expect it to ever work again LOL, unless you have all the tools in a workshop.

 

So, just make sure you dont have other problems, like head gasket, jammed thermostat, blocked radiator etc before you go shelling out on the ptu as it doesnt sound 100% like thats the problem to me.

 

If you do need one then there £150 all in from Luke at the Z centre, see trader forums.

TBH, your problem doesn't sound like PTU, as swbtt says, it's usually a dead cut. If it does turn out to be:

Cut around the back with a stanley knife / dremmel.

Off the PCB, there are several small ali wires. If it's a total failure, not one cyl, then the likely cause is that the main ground (2 wires together at one side) has come away from the bonding pad.

Try to lift them. If they lift, then you can resolder them with ali solder after cleaning the gunk off.

http://aus300zx.neuralmotion.com.au/tech/pturepair/pturepair.htm

when the water sprayed out, did it go all over the connectors for the tps,cas etc, it would seem a bit of a coincidence if you had 2 failures in 40mins and them not related. some of the water might have soacked a ht lead or a coil pack making you loose a cylinder or 2 perhaps??

Thanks guys. esp for the link...wondered where it was!

 

Hose came off due to loosening from a car park speed bump ten minutes before?? The engine hadn't quite reached normal temperature as it came off. The temperature guage never went above normal. Went up from cold to normal as it always does.

 

Head gasket problems unlikely as it's n/a with 52k miles. no oil / water mix. no previous problems. history ok. I will consider it a possibility though.

 

i've opened the PTU and all the connectors are fine. on no.2 though the little "L" shaped red/brown thingy appears to look charred right in the middle and the other 5 look fine (maybe i should pay membership so i can post pictures!!!). did sound like it was running on 5 cyls when it lost power.

 

i'll keep you updated what happens when i get my s2PTU in. (on knees praying)

Ok i've fitted the new s2 PTU and guess what.... it still doesn't start!!!! :rolleyes:

 

Quel surprise

 

It sounds exactly the same as it did before. still smell fuel from the exhaust on turnover so shouldn't be a problem with fuelling. Gonna do the ECU diagnostic in the next few hours but any pre-emptive ideas of what it could be??? :confused: :headvswal :cry:

 

HELP!!!

have you checked the connector on the CAS,TPS etc?, likely that they all got soaked with the hose coming off.

have you checked the connector on the CAS,TPS etc?, likely that they all got soaked with the hose coming off.

 

Don't think it'll still be wet from October which is when it happened. or could it.... (been in a dry garage for last 4-5 months)

 

Diagnostic said all is clear. Called Mr. RACman out for a laugh to get his opinion and he reckons it's head gasket. gonna start saving...

 

anyone done head gaskets before? got the manual but any problems not mentioned i am likely to encounter....?

Ok an update.

 

Tested the ignition and everything (including brand new s2 PTU) working ok. :cool: To try and get a clue as to what happened I looked at all the old spark plugs. All seemed newish. Plugs 2,4 & 6 seemed a bit coked up but nothing exceptional. Plug number one had slight rust / brown flakey bits around the rim but electrode ok. number 5 the same. Number 3 however was CAKED in rusty looking stuff. My car now starts with the new plugs in but is not very willing to start. I have to pump the fun pedal A LOT and at a particular frequency. Holding the pedal down doesn't do anything and neither does pumping is slowly. Seems like certain cylinders are firing up first and the others come in later. Water leakage into some of the cyls? Injector problem? Still to do a compression test.... Runs smoothly and idles ok once it going.

 

Is the compression tester I need 14mm thread size?

Does the description of plugs give anyone an idea whether it's the gasket?

 

Cheers in advance.