My colorado is now Undriveable.... :(

[Beau]

Hi Guys,

Recently my colorado has been suffering from what I think is a fuel starvation problem. I have been working out the possibilities and trying to solve it but I am getting no where. The problem is I would start it, and it will rev no more than 1500 rpm and sounds crap. Also a lot of white smoke....( fuel starvation) Also the fuel Blockage light comes on.

The things I have done so far.

- Removed Tank filter, checked for any metal corrosion ect.
-changed fuel filter in engine bay.
-Changed the Injector Pump strainer Pump
-Checked injectors
-Fuel is good.

I know fuel is getting to the Injector pump as it pulls it in and there is pressure. I cleaned out the injector pump stainer thinking it was blocked (which it was) and thinking that was the problem but it was not. As far as the uses manual says that is the only filter there so I cant see where a blockage could be. My theory is that the pump inside my be worn and therefore is not working efficiently.

Has anyone experienced similar problems before? Much help Appreciated.

 

[Chris]

Have you stood in the white smoke and breathed in? If you choke, it's smoke. If you get damp, it's steam and your head is cracked. Something not entirely unusual on a Colorado.

Can't say I can explain the water trap light though. Blocked injectors?

Chris

 

[BobMurphy]

The things I have done so far.

- Removed Tank filter, checked for any metal corrosion ect.
-changed fuel filter in engine bay.
-Changed the Injector Pump strainer Pump
-Checked injectors
-Fuel is good.

When you changed the diesel filter, did you thoroughly clean out the water trap/float and drain hose at the bottom ??

It does sound as though you have water in the fuel, though you say you have checked everything. If you drain the filter housing via the tube, is it just clean diesel that comes out ??
The float that triggers the fuel blockage light floats on water, but not on diesel, so something is making it rise - unless the problem is with the electronics & ECU.

Are all electrical connections around the pump clean and tight ??

Has anything else been done to the engine recently ?? I'm thinking pump/valve timing if the cam belt was changed, or if it has skipped a tooth. I'd spend a couple of minutes checking the timing marks on the cam, diesel pump and crankshaft just to be sure.

What mileage has the motor done ?? Another (unlikely) cause would be over-tight valve clearances.

Did the problem come on suddenly, or did it creep up on you ??. That might give us a clue.

Bob.

 

[Beau]

The things I have done so far.

- Removed Tank filter, checked for any metal corrosion ect.
-changed fuel filter in engine bay.
-Changed the Injector Pump strainer Pump
-Checked injectors
-Fuel is good.

When you changed the diesel filter, did you thoroughly clean out the water trap/float and drain hose at the bottom ??

It does sound as though you have water in the fuel, though you say you have checked everything. If you drain the filter housing via the tube, is it just clean diesel that comes out ??
The float that triggers the fuel blockage light floats on water, but not on diesel, so something is making it rise - unless the problem is with the electronics & ECU.

Are all electrical connections around the pump clean and tight ??

Has anything else been done to the engine recently ?? I'm thinking pump/valve timing if the cam belt was changed, or if it has skipped a tooth. I'd spend a couple of minutes checking the timing marks on the cam, diesel pump and crankshaft just to be sure.

What mileage has the motor done ?? Another (unlikely) cause would be over-tight valve clearances.

Did the problem come on suddenly, or did it creep up on you ??. That might give us a clue.

Bob.

I very much doubt the head is cracked as I have had a cracked head before and the car was very much driveable, and it is strong smoke, not water.

The Blockage light came on when I was on the motorway from a long trip, from there on I have been trying to solve it and it has got worse. I had fresh fuel which I fed into the injection pump and nothing changed to I would say that there is no fuel issue. The cam belt was changed a while ago as it only has 150,000 miles which is very low and it is well maintaned by me. I will check if everything is alighned.

If I however start it and put my foot down it will rev high as usual to 4400 but a bit un steady and when I lift my foot off it also stays there for a couple seconds before coming back down. A very unknown problem.... The only other thing I can think of is the ECU. But what is there to go wrong. My theory is that when the blockage light comes on it limits the amount of fuel coming on as there is a problem, but when you start it quickly then rev it, it forces the fuel through a blockage Im thinking and therefore the ECU does not pick up that there is a blockage. Overall a very strange problem.

 

[Leslie]

You could start by putting a new hose on the fuel inlet pipe on the fuel pump and put it in a drum of new diesel and see what happens , you will need at least 5lts due to the amount the pump pulls though , it will return to the rear tank ,
Try this and let us know how you get on ,

Cheers

 

[Lorin]

I'm thinking pump/valve timing if the cam belt was changed, or if it has skipped a tooth. I'd spend a couple of minutes checking the timing marks on the cam, diesel pump and crankshaft just to be sure. Bob.

I had similar symptoms with my 80 and it turned out to be the timing on the pump. Nothing had been touched prior either, it just went out! Getting the timing corrected solved it immediately

 

[Beau]

I'm thinking pump/valve timing if the cam belt was changed, or if it has skipped a tooth. I'd spend a couple of minutes checking the timing marks on the cam, diesel pump and crankshaft just to be sure. Bob.

I had similar symptoms with my 80 and it turned out to be the timing on the pump. Nothing had been touched prior either, it just went out! Getting the timing corrected solved it immediately

How exactly did you get the timing correct, and what would get the timing out on it. These Pumps are controlled by the ECU which measures the amount of fuel and the timing for the fuel to be injected, I dont think there is anything mechanically to go wrong other than wear in the pump, but I have never ever heard of Injector pumps on these cruisers failing. And I did try the external fuel and hose and no change.

 

[BobMurphy]

what would get the timing out on it. These Pumps are controlled by the ECU which measures the amount of fuel and the timing for the fuel to be injected, I dont think there is anything mechanically to go wrong other than wear in the pump, but I have never ever heard of Injector pumps on these cruisers failing.

When I changed my timing belt (at 120,000 miles) I found that the tensioning idler pivot had siezed and the belt was running slack. I put a new idler and tensioner in as well as the belt and its all fine - but I suspect a slack belt could jump a tooth or two putting everything out.

The pump is chain-driven from the crankshaft and the cam is belt-driven from the pump (so both run at half engine speed). The crank to pump timing shouldn't change, but pump to cam timing might.

Its a long-shot, but it only takes a few minutes to check if you haven't been in there for a while.

Bob.

 

[Beau]

PROBLEM FIXED!!!

I started it up and reved the hell out of it, on the limit for about5 minutes and then it drive like normal. So I am guessing that whatever was blocked has know unblocked it self by forcing more fuel in. I re-cleaned the filter in the injector pump and now she runs sooo smooth and and starts instantly. I would recommend everyone cleaning the Injector Pump. It is quick and a 5 minute job with small hands. Noticeably quicker on the road, much more smooth when at idle. Overall Im pleased shes back on the road.

 

[BobMurphy]

PROBLEM FIXED!!!

I started it up and reved the hell out of it

Ahhh the old "Mexican Tune-Up", used to work well on motorbikes in the '60s.





Bob.

 

[Beau]

PROBLEM FIXED!!!

I started it up and reved the hell out of it

Ahhh the old "Mexican Tune-Up", used to work well on motorbikes in the '60s.





Bob.

One slight probelm though, if I rev it past 4000 rpm and then take my foot off it will stay there for about 2 seconds before droping back down. Could this becasue a lot more fuel going through And If I have my foot all the way down it will actually red line to about 4600 rpm which before it was limiting it self to around 4400 I think.

What does everyone elses rev up to?

 

[adrianr]

Glad its fixed.

I would recommend everyone cleaning the Injector Pump. It is quick and a 5 minute job with small hands.

- might be nice if you could detail steps for the folks on here?

 

[Beau]

Glad its fixed.

I would recommend everyone cleaning the Injector Pump. It is quick and a 5 minute job with small hands.

- might be nice if you could detail steps for the folks on here?

Sure,

- Airbox needs removing, 3 12mm Bolts holding it in place, and then a screw driver for the clip.
- Unclip the return fuel pipe coming from the Pump (Just to make it easier)
- Undo all the wired clips you see from the Pump, its very easy to unclip and it is clear where they are go back as there is very little movement with the wires.
-There is a grey clip at the bottom of the spill control valve.

From the picture above the bit you are removing is the right bottom place where a clip should connect to (grey one). There is a 22mm spanner just behind it. It is clearer to see from the engine bay.

You then need a 22mm Spanner to Undo the BIG NUT on the close side to the pump, NOT the 19mm nut as this removes the plug and is not necessary.

Once out keep in a safe place as it is very delicate, note there is a rubber seal around the edge.

Now use a small flat screw driver or tweezer and yank/pull out the metal strainer.

Putting it back in is exactly the same. NOTE that the strainer goes in only one certain way.

Also to get most of the crap out, pump the fuel filter housing with the strainer out and let some fuel splash out, taking most of the crap in the pump out of it as well.

Put everything back together, Pump the filter to get fuel back into the pump and start her up!

If anyone wants more detailed instructions, PM me.

 

[KZJ90]

Hi Guys,

The problem is I would start it, and it will rev no more than 1500 rpm and sounds crap. Also a lot of white smoke....( fuel starvation)

I had just the similar problem recently in my LC90. Changed the filter, gave fuel directly to the pump from can and no... The returning hose was dry all the time. So, I found a tiny metal filter from below returning line banjo plug pipe. Cleaned it and yes, it promised but not good. Then I put pressured air to the returning line as long as it bubbles backwards. After that it worked well again.

So, there was some crap inside the pump which came out with pressured air.

 

[tim falce]

Glad its fixed.

I would recommend everyone cleaning the Injector Pump. It is quick and a 5 minute job with small hands.

- might be nice if you could detail steps for the folks on here?

Sure,

- Airbox needs removing, 3 12mm Bolts holding it in place, and then a screw driver for the clip.
- Unclip the return fuel pipe coming from the Pump (Just to make it easier)
- Undo all the wired clips you see from the Pump, its very easy to unclip and it is clear where they are go back as there is very little movement with the wires.
-There is a grey clip at the bottom of the spill control valve.

From the picture above the bit you are removing is the right bottom place where a clip should connect to (grey one). There is a 22mm spanner just behind it. It is clearer to see from the engine bay.

You then need a 22mm Spanner to Undo the BIG NUT on the close side to the pump, NOT the 19mm nut as this removes the plug and is not necessary.

Once out keep in a safe place as it is very delicate, note there is a rubber seal around the edge.

Now use a small flat screw driver or tweezer and yank/pull out the metal strainer.

Putting it back in is exactly the same. NOTE that the strainer goes in only one certain way.

Also to get most of the crap out, pump the fuel filter housing with the strainer out and let some fuel splash out, taking most of the crap in the pump out of it as well.

Put everything back together, Pump the filter to get fuel back into the pump and start her up!

If anyone wants more detailed instructions, PM me.

Which engine and year is this from?

 

[Beau]

My engine is about 14 years old, and it is the 3 litre 1kzte engine. Diesel.

 

[tim falce]

My engine is about 14 years old, and it is the 3 litre 1kzte engine. Diesel.

Not sure if that pump is the same as mine or the fact it has nothing connected makes it look different but on mine I can't see where you mean, is it the big housing that has a grey electrical socket on or the one with the main fuel feed pipe although these are opposite each other?

 

[Beau]

My engine is about 14 years old, and it is the 3 litre 1kzte engine. Diesel.

Not sure if that pump is the same as mine or the fact it has nothing connected makes it look different but on mine I can't see where you mean, is it the big housing that has a grey electrical socket on or the one with the main fuel feed pipe although these are opposite each other?

Its on the right side, towards where the injector pipes connect to, there is a grey plug fitting, This is where the Nut is to undo.

 

[tim falce]

Thanks for that, I'll take a look when I'm feeling brave. I was wondering if the strainer is blocked it may be causing my starting problems.

 

[Beau]

Thanks for that, I'll take a look when I'm feeling brave. I was wondering if the strainer is blocked it may be causing my starting problems.

It may but if your colorado is running fine at high speeds and not struggling up hills that should not be a problem.

I also took out the spill control valve (circle thing with a black top and a adjustment screw for fuel) Under this there is a filter which I also cleaned and now she is running sweet, starts up with one crank and runs and idles silky smooth. Well worth it!