Hard to Start

[Anonymous]

On the weekend i changed my intercooler from a front mount back to a top mount, with the help of Del and Mika. Everything went smoothly, with the exception of a flat battery from having the stereo on.

When starting the car, especially after putting in the tmic, it turns over many times before it fires, and then it will stumble for several seconds and sometimes stall before it comes good. Once it is running i have no problems, idles and drives perfectly, it is only when starting it. It varies on the severity of the problem, sometimes it takes a few goes to start it, and then sometimes it will start first pop. When it is hot it seems to be a little worse.

I have had this problem since i bought the car 4 months ago, but never as bad as it is at the moment. However the problem did dissapear before when i was using premium unleaded, i am using Optimax at the moment. I also have a surge tank and an uprated fuel pump.

I have checked the fuel system over for leaks but have found none. I have replaced the spark plugs recently as well. (It was doing this on the old plugs too). Could it be the timing set incorrectly :?:

Next tank of petrol i will go back to premium unleaded and see if the problem dissapears again.

Any help would be appreciated.

Kevin.

 

[Jon]

Hey Kevin,
starting at the beginning for checks.. loosely fitted hose on the top mount/fmic or a punctured/cracked hose or even a hole in the front mount/top mount?
dodgy maf?
water getting in the top of the plugs when you had the fmic on, now worked it's way into the leads. have you changed the leads/dizzy etc at all mate?
Jon

 

[Anonymous]

Thanxs Jon

I have checked over the tmic and hoses, found no problems. Removed and cleaned the MAF, checked the plugs etc, no problems.

The car still takes alot to start, although sometimes it fires first go :roll:
Someone else mentioned it might be the o2 sensor, i am getting the dump pipe replaced during the week as i am putting the aircon back in. The pipe currently only has 2 bolts holding it onto the turbo, i only discovered this the other day, some air may be leaking from the gasket, (although it can't be heard). I wonder if this might be something to do with it :?:

Kevin.

 

[Fast Guy]

Check your ht leads aren't earthing on the top mount somewhere. (Unlikely, but possible)

 

[sypher]

have u checked for un-metered air poss at intake to turbo or any pipes off/loose from air flow meter<---->intake of turbo or as prviously said above. fuel pressure prob did u adjust or change the reg' or carry out a clyinder compression check....someons said above to check ignition components poss water ingress or bad cap/arm or wrongly timed....

 

[Anonymous]

I have had this problem, ever since i dropped the gearbox and changed the clutch (car was in garage for about 2 weeks). I have had the injectors serviced twice, new fuel filter, tried another fuel pressure regulator, now have Bosch fuel pump, changed all fuel lines in engine bay, and even dropped the fuel tank and changed all fuel lines there.

When i dropped the fuel tank and changed all fuel lines (except the one that goes from fuel pump to top of tank) (new stanless steel hose clamps aswell) it fixed the problem for about 2 weeks then it started again. On the weekend i changed the hose that i hadn't changed (the one fro the fuel pump to the top of the fuel tank) with new clamps aswell and now im hoping for the best.

The problem that i have is that when the car has been off for a while (ie more than 15-20 mins and independent of wether the car is cold or hot) it takes a couple of cranks to start the engine and when it does its only doing around 200-500rpm and then after about 1-2seconds she comes to life. It drives, idles, boosts fine, only starting. But say if the engine is dead cold and manage to get it started it, then turn it straight off, and then start it again she fres first go, like it should. It is because of this that it has lead me to believe it was a fuel pressure problem.
I have to press the accelerator down if i want it to start properly, which shouldnt need, as its EFI. I have thought it was to do with fueling as i have checked spark plugs, AFM, etc. Im thinking now that it could be a sensor problem. I have a detonation sensor when i do the self diagnostics, so i might change that and see if it fixes it completely.

I might check the water temp sensor aswell, as i've heard when this sensors is on its way out it plays havoc on the engine.

Keep in touch to see if one of us fixes it first.

Gino

 

[sypher]

i suggest u get under the car and check the idle control which is bolted straight onto the head and has 2 small coolant hoses going to/from it, check the connector and wiring to this and for blocked/damaged pipes.

check the coolant temp sensor should be 300-330 ohm @ 80'c you'l need to warm it up obviously.

whilst your there check the knock sensor and plug aswell

when jacking the engine up and down you may have disturbed or stretched the wiring

 

[Anonymous]

Thanx guys, I think am thinking along the same lines as Gino, that it is a fuel problem. It's as if there is air seeping into the fuel system whilst the car is off for any period of time, and thus taking more cranking to get the fuel pressure back.

One thing i have noticed though, is if i pump the accelerator a few times with the ignition turned on, (but before starting the engine), the problem will almost dissapear. I know that pumping the accelerator will not make any difference to the fuel, being EFI, but it will cause the signal to change on the throttle position sensor. I will look into this further.

When doing a diagnostic i get all OK, (55), but as i've read in other posts this does not guarentee that all sensors are working correctly. I also still have the feeling that the timing might be out a little, :?: as using premium instead of Optimax causes the prob to virtually dissapear. :!:

I will let you know when i find the cause.

Kevin.

 

[Anonymous]

Thanx guys, I think am thinking along the same lines as Gino, that it is a fuel problem. It's as if there is air seeping into the fuel system whilst the car is off for any period of time, and thus taking more cranking to get the fuel pressure back.

One thing i have noticed though, is if i pump the accelerator a few times with the ignition turned on, (but before starting the engine), the problem will almost dissapear. I know that pumping the accelerator will not make any difference to the fuel, being EFI, but it will cause the signal to change on the throttle position sensor. I will look into this further.

When doing a diagnostic i get all OK, (55), but as i've read in other posts this does not guarentee that all sensors are working correctly. I also still have the feeling that the timing might be out a little, :?: as using premium instead of Optimax causes the prob to virtually dissapear. :!:

I will let you know when i find the cause.

Kevin.

Kevin

This is freaky, exactly the same problem and you and I came to exactly the same conclusions. I have thought about the throttle position sensor aswell, but if this was the case then it surely will cause idling problems, etc. personally i think like you said it was air seeping, or a leak somewhere in the fuel system. But as I have changed every single rubber fuel line with thicker, stronger lines, and all brand new hose clamps, and the fact I couldn't smell / see fuel leaking, it becomes very frustrating. And for some reason im positive its a fuel leak problem, and seeing as i cant smell / see the leak it must be a problem in the tank itself. The only thing i could think of was that when i chaged the fuel pump (to a bosch item) this needs a copeed threaded fitting, i just screwed it in the pump, but when i pulled it out last weekend, i put some teflon on the thread just in case, changed the fuel hose form the pump to top of the tank plus new hose clamps, and yesterday i started the car after 2 days of sitting in the garage and BINGO started first go without hesitation.

Not saying its fixed, but i certainly hope so, will have to do more testing, plus take it for a drive and see how things measure up. Will have a go at looking at my sensors aswell. Like someone said when i was changing the clutch (or you the intercooler) maybe a wiring plug jiggled and its not making a proper connectiong.

Gino

 

[Anonymous]

I have a Bosch fuel pump as well, but as far as i know it has moulded pieces on each end to slip the hose and clamp over. I will have a closer look in the next day or so.

I will keep checking back here and provide progress reports, (if i have any ), we will work it out eventually.

Kevin.

 

[gotoinstant-redline]

fuel pump was my thought too.
the R primes the pump for 5 secs to get the rail presure up on startup. turn teh key and let it sit at the on position for 5 secs then try and start it.
i had the same prob on a 200sx and it turned out to be that the wires to the pump were not on properly.

also check the pump relay. this can go (not that i have ever seen one gone) but its another point to check.

good luck.

L.

 

[Anonymous]

I also have a Bosch pump in the boot, and i can hear it prime the system each time i start the car, i always wait until the pump stops before turning the motor over.

Yesterday i struck another problem, may or may not be related - the car began to hessitate really badly when trying to boost, to the point where the car could not gain any speed at all. I did the usual, checked the plugs (and regaped them from 0.9mm to 0.8mm) and took off the distributor cap and checked the rotor and cap itself. The rotor was OK but the posts in the cap are white and pitted.

I was thinking if when starting because the spark is from the battery only that it would have trouble until it finally fires and then the alternator takes over and the voltage increases? I think someone in a earlier post was saying something along this line too. Anyways i am going to replace the cap over the next week or so and see if this makes any difference.

The hessitation problem is now gone after cleaning the cap and regapping the plugs. Although it idles a little rough. The starting problem remains.
Kevin.

 

[gotoinstant-redline]

have you checked the o2 sensor and the maf??
there are lots of posts in the past about these, so please have a look in the history.. but basicly if teh maf isnt doing its job then nothing works and the o2 sensor is important.

simply timing??
crack open your ecu and have a look for extra chips.. if there is another board in there with 2 chips on it then you are not running a standard map. this might be a problem.. but you need to get outhe soldering iron to revert back to stock.. so best have a look, see whats there and report back before chopping anything in 2.

dumpvalve? if you have one.. even the stock one.. make sure its on tight and not leaking. maybe the valve is worn out? can you get you rear near it on idle and then rev the car with your hand on the gas cable? you should be able to feel/hear a leak from it if it is..

coil? maybe its on its way out??

again good luck and report back with as much info as you can, we'll keep trying to think of new fixes..

have you had a compression test done? VERY VERY cheap and the aa/rac will do them for free at the road side if you are a member.

L.

 

[Anonymous]

Progress report . . . .

The hesitation problem returned worse than ever the other day, and as well as that the CD player kept switching on and off for no reason. I checked the fuses, including the 2 main fusable links and found one of em to be chargrilled but still working - kinda.

I replaced the link and all the problems have vanished. The car sometimes is a little hard to start, but not nearly as bad as was prviously. I think this might have been the main culpret for the hard starting as the spark was weak from the faulty fusable link.

Gino it might pay to look at your links and make sure the connections are clean. It was the 60amp link that was cactus, only because the connection was bad, not due to overloading.

I will continue to post updates if i find anything else.

Kevin.