My Hiace has no power

[barnsleyer]

Hi all, I am new here, I have a 2003 Hiace 2RZ-E that has a power problem

my engine is only happy at about 10 - 20% throttle ? which is very slow on acceleration. If I push down the pedal further it makes no difference only alters the engine tone

The engine revs up ok while standing and sounds ok but when asked to go is very poor on power

I do have a crack in my exhaust manifold which is getting changed soon when I locate one

Any ideas anyone its like driving with the handbrake on

Many thanks
Chris

[timsrv]

Sounds like restriction in the air intake and/or exhaust. Check the air filter to make sure it's clear and check the EGR parts to see if anything is melted. If you see overheated or melted parts on or around the EGR, this is a big indication that your catalytic converter is plugged up. Tim

[barnsleyer]

Sounds like restriction in the air intake and/or exhaust. Check the air filter to make sure it's clear and check the EGR parts to see if anything is melted. If you see overheated or melted parts on or around the EGR, this is a big indication that your catalytic converter is plugged up. Tim

Thanks Tim, We have already replaced a a badly eroded hose between the airbox and inlet manifold, the vacuum was collapsing the hose almost flat and we got a slight improvement,
We have owned the van for 12 months and it has never had any real power but it is getting worse, We have just had the cylinder head replaced as there were 2 cracked exhaust valves on 3 & 4.

We were informed the manifold has a crack in it and are currently sourcing one this week

I dont know what the EGR and its parts are and its location but I will google it

We also run on LPG which is ok apart from loud backfires sometimes after a short idle at traffic lights followed by a stall

The van has done 430,000 kms but apart from this problem is a great van

Thank you most sincerely for your reply

Chris

[timsrv]

If tuned properly you can expect ~10% loss of power from running LPG, but that still leaves ~90% which should be plenty. LPG does throw a variable in there with the method of delivery. If will not make power if it isn't getting sufficient gas flow, so I'd also try to verify that system is working correctly. Your van is a different animal than our US versions and the LPG thing makes it even more strange (to me) so what I've offered so for is about all I have. I am interested though, so please report back as to your progress. Thanks for being part of TVT! :thmbup: Tim

[timsrv]

I'm not sure how your EGR (Exhaust Gas Recirculation) is configured, but the modulators all pretty much look the same. Here's a picture of one (round black plastic part on the right). When you find yours check it closely for signs of overheating. Also you can go to the tail pipe and have somebody rev the engine. There should be a good "blast" of exhaust out the back when it's revved. If there is very little or no flow out the exhaust, then I'd look closer at the catalytic converter. Tim

http://2.bp.blogspot.com/-QTliSVoUaTk/VCH55defN4I/AAAAAAAABKw/sXNA-3HejtI/s1600/03-EGR_vacuum_modulator.jpg

[barnsleyer]

Thank very much for that tim,
My radiator top tank burst yesterday so its back in for repair

I sent it to the garage who fitted my new cylinder head last weekend, I only got it back last sunday

Could they have done anything wrong to cause this problem by swapping the head ? like valve timing or ? Just wondering if an engine would run but poorly with the cam not aligned properley ?

[timsrv]

Sure, not only is it possible, but likely. If a vehicle starts running bad or performance decreases immediately following a major service, then the service and the problem(s) are most likely linked. Could be a coincidence, but most of the time I would suspect the mechanic screwed something up or overlooked something (it happens to the best of us). Lots and lots of possibilities here. Be sure to tell them and have them test drive it. If it's their fault, they should remedy for free (assuming they are reputable). Tim

[barnsleyer]

Thanks for your super quick reply

I received a call from the mechanic whos says he has fixed it ???
He says he has replaced the rubber pipe /hose between the airbox and manifold and also replaced 1 x spark plug lead
He cannot test it on the road as the radiator has blown but says it is now ok, I will believe it when I see it ?

I can believe the air pipe collapsing due to perishing restricting the airflow but changing 1 lead ??

Thanks again
Chris

[barnsleyer]

Thanks Tim
Fixed it, was the air pipe between the air box and manifold that was perished and collapsing, hard to see under the seat,

Now I have a new problem,
I can hear a sucking noise fromt he inlet manifold area and my throttle has a mind of its own, it goes from idle to about 2000 rpm al the time , up down,

Any ideas, sounds like a sensor ?
Thanks

[timsrv]

I'm too old school to answer these type questions as I don't have any familiarity with that engine. My guess is you have a vacuum leak, an air intake leak, or perhaps a failed sensor. Have you scanned it to see if there are any trouble codes?

[Carbonized]

2003 motor, should be OBDII equipped? Like Tim said the codes should tell you or your mechanic at least what area to look into.

[barnsleyer]

Thanks again
How and where do I get an error code please

[barnsleyer]

2003 motor, should be OBDII equipped? Like Tim said the codes should tell you or your mechanic at least what area to look into.

I suppose I have to buy something to get this code do I, like an instrument ?
Many thanks

[barnsleyer]

Found it thanks

A core plug had blown out of the throttle body, now I just have to get a replacement, thanks all