RangeRovers.net Forum banner

1 - 4 of 4 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
hi everyone, we have a 3.5efi and on start up we get steam/condensation from exhaust it is getting a high hydrocarbon reading at the smog staion, checked all cylinders and get 120psi on a compression test, thought about the cats grrrrr, but am wondering if it is maybe the head gasket. it does lose some coolant over time but has no oil contamination, running out of time to fix as i got a fix it for taking it out for a run with out of date tags....bigger grrrrr, any thought would be appreciated
cheers Paul
 

·
Registered
Joined
·
272 Posts
Paul, if you're getting vast, billowing clouds of sickly sweet smelling steam, then your head gasket is leaking into a combustion chamber. If you're getting a little steam at startup on a cool morning and the steam becomes invisible within 10 minutes of startup, then your engine is probably working normally.

High hydrocarbons in the exhaust means that you've got unburned fuel in your exhaust. Is your EFI light on? If so, then your fuel injection computer is beyond the range at which it can compensate for normal wear and tear, and you need some maintenance. If the EFI light isn't on, then you may need new oxygen sensors. They become less sensitive over time, and the recommendation is to replace them every 80,000 miles or so. There is a timer built into the Range Rover that lights a "Check Engine" light when it is time to replace the oxygen sensors. There are many other conditions that can create excessive hydrocarbon emissions, like an ignition miss, leaking fuel injectors, a malfunctioning fuel pressure regulator, vacuum leaks, and many more.

If you have the repair manuals and the tools, then work the problem methodically. If you don't, take your Rover to a shop that is equipped for working on them. They can probably diagnose the problem in less than an hour of billable time, and get you an estimate for the repair cost.

Good luck,
Scott
 

·
Registered
Joined
·
6 Posts
Discussion Starter #3
Thanks Scott, well i changed the o2 sensors, cleaned the flame arrestor, changed the air filter ,plugs a couple of dodgy plug leads, Plugs looked as expected when i took them out, efi light was on but after cleaning the flame arrestor it hasn't come on again, it seems so stay steamy...not much though and after a while becomes intermitent once she's warmed up but the compression is consistent throughout, haven't checked all the vac lines though and i will but would that be enough to make the readings excessivly high? thanks Paul
 

·
Registered
Joined
·
272 Posts
Vacuum leaks do all sorts of freaky things. If you're trying to track down the cause of rich running, you really can't jump to conclusions. If you have an EFI light on, the only cause is that the feedback circuit disagrees with the inputs to the fuel map solution so badly, by such an egregious error, that the designers couldn't compensate for the difference. If your truck is running without its EFI light on, then it might be possible that it is running completely within tolerances and is now capable of passing an emissions test. I wouldn't rush right out and get it tested at an official station just yet, especially if you live in a state that requires documented proof that you've spent more than $XXX on a repair from a certified mechanic, like California, or only allows two failures before condemning the car. In states like that, you can often slip the tester some money to run a test "off the record" to see if you'll pass first, then if that result looks encouraging go for a test "for the record." That's saved my bottom a few times when I lived in California. Oregon isn't quite so regimented... you can pay and fail as many times as you want to pay for the test, but you won't get a smog certificate until you pass. I don't know about where you are, so it could be very different.

Scott
 
1 - 4 of 4 Posts
Top