Hard Starting - 1990 Cherokee
 

A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
inline 6.
Every time he tries to start it after it's sat for awhile it takes a looong
time to finally fire. Time is 8-10 seconds. With winter coming, he's
concerned with keeping enough battery capacity available on cold Canadian
winter mornings.

Any quick things we should check out over a couple of Canadian beers? The
truck has just over 50K miles and is otherwise in fantastic shape.

Jeff Falkiner
Ontario, Canada

Re: Hard Starting - 1990 Cherokee
 

Probably the anti-drainback valve in the fuel line leaking, allowing the gas
that is supposed to stay in the fuel injector and fuel rail to drain all the
way back down into the gas tank. The delay in starting is the time the fuel
takes to get back up to the fuel injectors from the gas tank.

Jerry
--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.cox.net/jerrypb/
"Jeff Falkiner" <nospam.falkiner@stopspam.netrover.com> wrote in message
news:oA%dd.81468$vO1.459004@nnrp1.uunet.ca...
>
> A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
> inline 6.
> Every time he tries to start it after it's sat for awhile it takes a
> looong
> time to finally fire. Time is 8-10 seconds. With winter coming, he's
> concerned with keeping enough battery capacity available on cold Canadian
> winter mornings.
>
> Any quick things we should check out over a couple of Canadian beers? The
> truck has just over 50K miles and is otherwise in fantastic shape.
>
> Jeff Falkiner
> Ontario, Canada
>
>

Re: Hard Starting - 1990 Cherokee
 

Probably the anti-drainback valve in the fuel line leaking, allowing the gas
that is supposed to stay in the fuel injector and fuel rail to drain all the
way back down into the gas tank. The delay in starting is the time the fuel
takes to get back up to the fuel injectors from the gas tank.

Jerry
--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.cox.net/jerrypb/
"Jeff Falkiner" <nospam.falkiner@stopspam.netrover.com> wrote in message
news:oA%dd.81468$vO1.459004@nnrp1.uunet.ca...
>
> A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
> inline 6.
> Every time he tries to start it after it's sat for awhile it takes a
> looong
> time to finally fire. Time is 8-10 seconds. With winter coming, he's
> concerned with keeping enough battery capacity available on cold Canadian
> winter mornings.
>
> Any quick things we should check out over a couple of Canadian beers? The
> truck has just over 50K miles and is otherwise in fantastic shape.
>
> Jeff Falkiner
> Ontario, Canada
>
>

Re: Hard Starting - 1990 Cherokee
 

Probably the anti-drainback valve in the fuel line leaking, allowing the gas
that is supposed to stay in the fuel injector and fuel rail to drain all the
way back down into the gas tank. The delay in starting is the time the fuel
takes to get back up to the fuel injectors from the gas tank.

Jerry
--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.cox.net/jerrypb/
"Jeff Falkiner" <nospam.falkiner@stopspam.netrover.com> wrote in message
news:oA%dd.81468$vO1.459004@nnrp1.uunet.ca...
>
> A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
> inline 6.
> Every time he tries to start it after it's sat for awhile it takes a
> looong
> time to finally fire. Time is 8-10 seconds. With winter coming, he's
> concerned with keeping enough battery capacity available on cold Canadian
> winter mornings.
>
> Any quick things we should check out over a couple of Canadian beers? The
> truck has just over 50K miles and is otherwise in fantastic shape.
>
> Jeff Falkiner
> Ontario, Canada
>
>

Re: Hard Starting - 1990 Cherokee
 

Jeff Falkiner did pass the time by typing:
> A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
> inline 6.
> Every time he tries to start it after it's sat for awhile it takes a looong
> time to finally fire. Time is 8-10 seconds. With winter coming, he's
> concerned with keeping enough battery capacity available on cold Canadian
> winter mornings.
>
> Any quick things we should check out over a couple of Canadian beers? The
> truck has just over 50K miles and is otherwise in fantastic shape.

Fuel rail pressure. Fit a gauge to it and see if it stays about 32 psi and
doesn't drop more than 4-5psi over a few hours. If it does you either have
a leaking pressure regulator (front of the fuel rail), drainback valve
(on the fuel pump), or a leaking fuel injector. further diagnosis isn't too
hard but you need a set of hoses built for the job.

In the mean while you could try turning the key on, wait for the pump to
cycle, then off, then on again. That cycles the pump and gets fuel and
pressure back into the rail.


--
-- DougW -- 93 ZJ 4.0 http://members.cox.net/wilsond
HESCO Supercharger - 300W IASCA Stereo - Edelbrock IAS Shocks
Gibson Exhaust - rear DCpower - custom gauge install - Stillen Rotors
Banks Header - and BEER, in the fridge!

Re: Hard Starting - 1990 Cherokee
 

Jeff Falkiner did pass the time by typing:
> A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
> inline 6.
> Every time he tries to start it after it's sat for awhile it takes a looong
> time to finally fire. Time is 8-10 seconds. With winter coming, he's
> concerned with keeping enough battery capacity available on cold Canadian
> winter mornings.
>
> Any quick things we should check out over a couple of Canadian beers? The
> truck has just over 50K miles and is otherwise in fantastic shape.

Fuel rail pressure. Fit a gauge to it and see if it stays about 32 psi and
doesn't drop more than 4-5psi over a few hours. If it does you either have
a leaking pressure regulator (front of the fuel rail), drainback valve
(on the fuel pump), or a leaking fuel injector. further diagnosis isn't too
hard but you need a set of hoses built for the job.

In the mean while you could try turning the key on, wait for the pump to
cycle, then off, then on again. That cycles the pump and gets fuel and
pressure back into the rail.


--
-- DougW -- 93 ZJ 4.0 http://members.cox.net/wilsond
HESCO Supercharger - 300W IASCA Stereo - Edelbrock IAS Shocks
Gibson Exhaust - rear DCpower - custom gauge install - Stillen Rotors
Banks Header - and BEER, in the fridge!

Re: Hard Starting - 1990 Cherokee
 

Jeff Falkiner did pass the time by typing:
> A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
> inline 6.
> Every time he tries to start it after it's sat for awhile it takes a looong
> time to finally fire. Time is 8-10 seconds. With winter coming, he's
> concerned with keeping enough battery capacity available on cold Canadian
> winter mornings.
>
> Any quick things we should check out over a couple of Canadian beers? The
> truck has just over 50K miles and is otherwise in fantastic shape.

Fuel rail pressure. Fit a gauge to it and see if it stays about 32 psi and
doesn't drop more than 4-5psi over a few hours. If it does you either have
a leaking pressure regulator (front of the fuel rail), drainback valve
(on the fuel pump), or a leaking fuel injector. further diagnosis isn't too
hard but you need a set of hoses built for the job.

In the mean while you could try turning the key on, wait for the pump to
cycle, then off, then on again. That cycles the pump and gets fuel and
pressure back into the rail.


--
-- DougW -- 93 ZJ 4.0 http://members.cox.net/wilsond
HESCO Supercharger - 300W IASCA Stereo - Edelbrock IAS Shocks
Gibson Exhaust - rear DCpower - custom gauge install - Stillen Rotors
Banks Header - and BEER, in the fridge!

Re: Hard Starting - 1990 Cherokee
 

DougW wrote:

> Jeff Falkiner did pass the time by typing:
>
>>A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
>>inline 6.
>>Every time he tries to start it after it's sat for awhile it takes a looong
>>time to finally fire. Time is 8-10 seconds. With winter coming, he's
>>concerned with keeping enough battery capacity available on cold Canadian
>>winter mornings.
>>
>>Any quick things we should check out over a couple of Canadian beers? The
>>truck has just over 50K miles and is otherwise in fantastic shape.
>
>
> Fuel rail pressure. Fit a gauge to it and see if it stays about 32 psi and
> doesn't drop more than 4-5psi over a few hours. If it does you either have
> a leaking pressure regulator (front of the fuel rail), drainback valve
> (on the fuel pump), or a leaking fuel injector. further diagnosis isn't too
> hard but you need a set of hoses built for the job.
>
> In the mean while you could try turning the key on, wait for the pump to
> cycle, then off, then on again. That cycles the pump and gets fuel and
> pressure back into the rail.
>
>

When my fuel pump was dying (91 XJ, 4.0) last year, it took longer and
longer to start until one day when it just didn't. In my case, the
regulator and drainback valve were fine. We replaced the pump and filter
and everything is now tickity-boo.

Regards,

DAve

Re: Hard Starting - 1990 Cherokee
 

DougW wrote:

> Jeff Falkiner did pass the time by typing:
>
>>A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
>>inline 6.
>>Every time he tries to start it after it's sat for awhile it takes a looong
>>time to finally fire. Time is 8-10 seconds. With winter coming, he's
>>concerned with keeping enough battery capacity available on cold Canadian
>>winter mornings.
>>
>>Any quick things we should check out over a couple of Canadian beers? The
>>truck has just over 50K miles and is otherwise in fantastic shape.
>
>
> Fuel rail pressure. Fit a gauge to it and see if it stays about 32 psi and
> doesn't drop more than 4-5psi over a few hours. If it does you either have
> a leaking pressure regulator (front of the fuel rail), drainback valve
> (on the fuel pump), or a leaking fuel injector. further diagnosis isn't too
> hard but you need a set of hoses built for the job.
>
> In the mean while you could try turning the key on, wait for the pump to
> cycle, then off, then on again. That cycles the pump and gets fuel and
> pressure back into the rail.
>
>

When my fuel pump was dying (91 XJ, 4.0) last year, it took longer and
longer to start until one day when it just didn't. In my case, the
regulator and drainback valve were fine. We replaced the pump and filter
and everything is now tickity-boo.

Regards,

DAve

Re: Hard Starting - 1990 Cherokee
 

DougW wrote:

> Jeff Falkiner did pass the time by typing:
>
>>A good buddy recently bought a 1990 Cherokee Limited with the 4.0 litre
>>inline 6.
>>Every time he tries to start it after it's sat for awhile it takes a looong
>>time to finally fire. Time is 8-10 seconds. With winter coming, he's
>>concerned with keeping enough battery capacity available on cold Canadian
>>winter mornings.
>>
>>Any quick things we should check out over a couple of Canadian beers? The
>>truck has just over 50K miles and is otherwise in fantastic shape.
>
>
> Fuel rail pressure. Fit a gauge to it and see if it stays about 32 psi and
> doesn't drop more than 4-5psi over a few hours. If it does you either have
> a leaking pressure regulator (front of the fuel rail), drainback valve
> (on the fuel pump), or a leaking fuel injector. further diagnosis isn't too
> hard but you need a set of hoses built for the job.
>
> In the mean while you could try turning the key on, wait for the pump to
> cycle, then off, then on again. That cycles the pump and gets fuel and
> pressure back into the rail.
>
>

When my fuel pump was dying (91 XJ, 4.0) last year, it took longer and
longer to start until one day when it just didn't. In my case, the
regulator and drainback valve were fine. We replaced the pump and filter
and everything is now tickity-boo.

Regards,

DAve