SLOW STARTING OR NOT STARTING HOT

[tc ozzie]

HI THERE
please can any one help me i have changed my alternator,starter and battery
just recently

and the car starts first thing in the mornings when i go to work 12hrs later when i leave work it starts up first thing

but when i get home and turn the car off
if i happen to go out again say 5 minutes later it will not start or it will but with the felling of having a flat battery now when i check the car is charging it is from both the alternator end and the battery end no problems there
i have also replaced the relays with the updated kits from deloreans the full kit
i have replaced plugs oils filters and good nows what else ive replaced but still no joy

i have fittted the heat shield for the starter this was missing now there

and now i just dont know what else to check

any ideas please

thanks
tony

[steve.s]

hi

i would guess this could be the usual hot start problem, ie fuel pressures.

have you considered the accumulator?.

try warming up and if struggles to start, jump the cold start valve (swap lead from the regulator.

this will make the csv inject fuel in (as in as if the car is cold).

take off the lead once started otherwise the cold start valve will keep pumping in fuel, and the exhaust will get very smokey (and petrol smelly!)

let us know if this works.

the other one to do, take off the air intake, hold the fuel flap down 5mm, then try to start.

other issues could be a fault pressure regulator at the fuel pump, poor fuel pump, collapsed fuel hose in the tank so notkeeping warm pressure.

also the fuel distributor has a fuel pressure valve in.
see specialtauto site for more details.

if the battery was not charging, then the light would likely to be on.

if it struggles to start, then does a jump kit make it start instantly?. if it does then it may more be a voltage drop problem, if an early car, there is a fix (in one of last years doc mags), so you could check the resistors at the back left hand side of the engine.

hope this helps and keep us posted.

[NickT]

What vin have you got?

Early vins (to about vin2000 I think) had an issue with starting if the voltage was down to a certain level.

Th mod is to use a short length of wire and to modify the starter motor relay so that the current going to the starter solenoid doesn't come from the ignition switch but from another circuit.

This is covered in a previous magazine.

If the starting issue occurs when the engine is hot then it could be down to the accumulator as steve.s sugests. To help, the cold start valve and control pressure regulator electrical connectors are colour coded:

Remove blue electrical connector from cold start valve.
Remove grey electrical connector from the control pressure regulator (near oil filler on left hand rocker cover)
Connect grey electrical connector to cold start valve.

Then do as what steve.s suggests.

Another point to note, when you put the ignition key to position 2 it should run the fuel pump for 2 to 3 seconds to prime the fuel system ready to start. If it does:

Put the key to position 2 to run fuel pump.
Put key to position 0
Put the key to position 2 to run fuel pump.
Put key to position 0
Put the key to position 2 to run fuel pump.
Put key to position 0
Put the key to position 2 to run fuel pump.
Try to start the engine.

If it starts better/ first time then this is a rough indication that there is a a fault in the fuel accumulator (although a fuel ressure test will confirm this).

If the fuel system doesn't prime for 2 to 3 seconds then the fuel pump relay will need looking at.

Good luck.

NickT.

[tc ozzie]

my vin or chasis number i think is an early one ive had a new fuel pump with new hoses and all that
these have been replaced also recently the pump does run alot though i have noticed but not all the time some times when ya turn the key the pump comes on then stops first thing but sometimes you will get in the car and turn the ignition on and the pump keeps running so i think that needs to be checked
or is this normal ive had the car about a year sofar it has been very reliable
exept when it slow starts or fails to start giving the impession of a flat battery but its new

i was going to change the alternator to the 110amp one its an origanal one i have on there at the moment but new

[Rich H]

Standard hot start diagnostics first

When the engine is nice and hot, turn off ignition and remove air filter box.

Gently press the metering flap down...any resistance? If not then your problem is either the fuel accumalator, primary pressure regulator, or check valve in the fuel pump.

[PJ Grady (Europe)]

Hey Tony,

As you're so close - you're welcome to pop down at some point and have the car checked out. We have accumulators, etc if it turns out to be the problem.
We've also got a fuel pressure testing kit to hand....

All the best.....keep that Trans Am warm for me!

Darren

[NickT]

Might be quicker to just take it to PJ Gradys and have the fuel pressures tested if you are close by. At least they would be able to narrow it down to either fuel or electrical.

NickT

[tc ozzie]

right then ok pj when can i come down to yours im off wednesday and thursday this week if this is ok let me know

[PJ Grady (Europe)]

Hey Tony,

Give us a ring on Thursday (01268 680278). Should be able to look at it then.

Cheers

Darren

[tc ozzie]

ok no worrys call ya then