Starting Issues... Did The Autosparggky Kill Something?

[madmoomoo]

Hi skyliners!

It would appear as though an autosparky has done something that has broken some unknown thing in my car. Can ANYONE help?

Problems started when my alarm went nuts and used to engage and immobilise the car when i was driving (yeah, not very fun), so i went to the local autosparky, and he said that alarms can go a bit mental with age, so i said just rip it out and put a new one in.

The car is a 93 r33gtst, and he put some standard alarm in, pretty basic, i didn't want anything complicated

When i went to pick the car up, it didn't start properly, and he said it might be flooded and just to give it some gas while starting, which i did, and it started. Since that day, the car has never started successfully first time using just the key (and no accelerator pedal).

My initial thought was that he'd not soldered something properly to the fuel pump or the alarm unit was faulty, so i took it back to him and asked him to check his work.

The symptoms currently are:

having to pump the accelerator to start.

usually cranks over about 5 secs or so, sounding like it isn't getting enough fuel

it takes 2-6 attempts to start (cold more so than hot, but even when recently stopped, takes more effort than it ever used to)

after getting car back the second time, would sometimes idle at about 2k for the first trip of the day

if i quickly do a u-turn, it'll often conk out, after revving, then taking foot off accelerator and also using powersteering...

Aside from this, the car drives well.

My battery was changed about 6 months ago, and was fully charged when tested and the alternator was rebuilt at the start of the year as well and is all good

So, when he had it the second time, i asked him to check the fuel pump and do an overall looking into. This is what he did:

fuel pump was ok... had enough pressure

pressure regulator was ok

coolant temp sensor was bung so he replaced

he got afm rebuilt (at a cost of bloody $300 bucks or something, but he did this before i knew about it... grrr)

all wiring he said was ok.

he said that when left overnight, the fuel pressure dropped, and said that it should maintain the pressure when left overnight. This sounds about right to my novice ears, cos the car feels as though it's just not getting enough juice when it starts. To me it feels like a fuel thing, but could well be the ecu, or whatever it is that controls the idling when under load etc.

I'm really not sure where to go with this. my knowledge is exhausted, but it's rather annoying that the car has always started first time everytime, and will now not ever start the first time.

Has anyone got any suggestions for what it could be or what i could try? my searching on these forums has pretty much just pointed to either fuel pump or afm, both of which appear to be fine...

[axe s]

check your AAC valve is working properly... it is the thing that controls the idle... maybe give it a clean and reset you idle...

[700HP-GTR33]

Bad fuel pump.....?

Clogged fuel filter...?

Bad..or stuffed battery....?

Battery would be my first guess......You have had the alarm drain it a number of times....

Incorrect..or slightly lower power delivery can also cause this problem.

[madmoomoo]

Hi guys,

I had a new batt put in, and the sparky had charged it when testing.

The fuel filter i changed before taking back to him the second time, and according to him the fuel pump was building enough pressure. I don't know enough about the fuel system to be able to diagnose this, but the sparky seemed convinced the pump is fine.

he also check spark plugs and coilpacks as well...

i'll check the AAC valve today while i'm home. i don't really know about this, but i'll search how to do it.

I'm thinking though, if it's a physical valve that controls the idle, if i'm starting the car with my foot flat on the accelerator, then wouldn't this valve be fully open anyway? (i don't even know what the AAC valve is, but i'll look it up right now).

when it's cranking over, the power sounds fine, i can hear the thing turning over, but it sounds and feels like it's not getting enough fuel, then when it finally gets enough, it comes to life.

very confusing, but geez it's annoying! my poor car used to start first time every time!

[madbung]

Geez thats a weird one....my first guess would be for some reason there is too much resistance between ignition and immobiliser.

Check voltage each side of the immobiliser.

Although as you said it does drive ok, so fuel system would be my next stop.

Before all else, try an ecu reset...disconnect battery, apply brake pedal for a minute or 2, reconnect battery start, let idle for 10-15 min then go for a thrash. Possibly when the ecu was last disconnected (battery) it probably wasn't given time enough on start up to re-learn its sheet properly on idle.

Edited June 15, 2008 by madbung

[madmoomoo]

Ok, this is strange...

After last weekend (didn't drive anywhere on sun), come monday morning, i had remembered the sparky saying something about the diff between having the coolant temp sensor plugged in and not, so i popped the bonnet and unplugged it, turned the key, and voila! instant start with barely cranking a second time! no foot on the pedal and no multiple attempts.

SO... i drove to work ok, went to park, did a U-turn quickly, and in the process (like has often randomly been happening lately), the thing stalls, but i was pretty much in place, BUT, the thing wouldn't start! tried 8 times to start the car, opened the bonnet and plugged sensor back in and it started!

Anyway, long story short, i tried again yest, and same story, started fine, but then after filling up with petrol that night, wouldn't start until sensor plugged back in.

??

AND that's not the worst of it. Now, most of the tiem when i drive, when it starts to build boost, it shudders and feels like it's shakey and losing power, so needless to say as soon as i feel that i ease off the accelerator.

it's not all the time, sometimes only at the start of the journey, sometimes only at the end. tonight after work was the whole way home.

anybody have any ideas? is my ecu screwed or something? any help would be awesome, cos this is completely beyond my small brain...

[madmoomoo]

ooh.

been doing more searching. anyone got any comments?

http://www.skylinesaustralia.com/forums/Wh...&hl=shudder

i DID do a gentle wash on top of the engine i think last weekend. (by gentle i mean had oil there, so sprayed degreaser, then tissues to mop up, then tipped waterbottle over it..)

and http://www.skylinesaustralia.com/forums/Ca...&hl=shudder

the sparky said he tested fuel pump, coilpacks & regulator. but seeing that he possibly broke something in the first place... should i go and check any of these things?

[madmoomoo]

ooh.

been doing more searching. anyone got any comments?

http://www.skylinesaustralia.com/forums/Wh...&hl=shudder

i DID do a gentle wash on top of the engine i think last weekend. (by gentle i mean had oil there, so sprayed degreaser, then tissues to mop up, then tipped waterbottle over it..)

and http://www.skylinesaustralia.com/forums/Ca...&hl=shudder

the sparky said he tested fuel pump, coilpacks & regulator. but seeing that he possibly broke something in the first place... should i go and check any of these things?

[blind_elk]

Would seem the replacement temp sensor was faulty - the ECU thinks the engine is hot, when it's actually cold. So tries to start a "hot" engine.

You need to reconnect the sensor after the engine starts, otherwise the ECU always thinks the engine is cold, and dumps fuel in there - fuel economy -> crap.

[madmoomoo]

Ok, so i went to check my coil packs and spark plugs today, and when pulling things apart, rather obvious, was the fact that the autosparky has cracked the metal frame that the coilpacks screw into (i'll attempt to add pic). And because i had given the top of the engine a light clean last weekend, degreaser and water had gotten in though the crack, and was pooled around the sparkplug in cylinder 3 (from the front). before going any further, i used paper towel to soak up any moisture i could get to so that it didn't just empty into the cylinder as i removed the sparkplug.

Q: Will i have to try and get this fixed/replaced? or can i just go along, knowing that i can't get water in there?

Next thing: The spark plugs i pulled out were all pretty much black, and the 3rd one was wet (which i knew was going to happen due to the events above). I noticed that most of the spark plugs weren't screwed in very hard at all, and were possibly loose. I'll pick up some new ones 2mo just to eliminate them as a prob.

While i had things open, so i measured the resistance of the coilpacks. I hadn't done this before, but i think i did it right. resistance from the front cylinder to the back were as follows:

12.5

12.1

11.7

12.8

12.3

12.8

Does this look ok?

So, what should i do next folks? i'm leaving the plugs out overnight just so things can dry up properly...

any help would be greatly appreciated.

ps. pic of the spark plugs is closest plug to front of car at right side of pic. rest in order...