| Author | Message | ||
     Brad Russell (Bradnc) Member Username: Bradnc Post Number: 225 Registered: 03-2002 |
My truck isn't running well and I have the OBDII Computer Software from Alex Pepper. If someone else has the same software and knows their truck is running well, I'd like it if you could send me the file of your truck so that I could compare it against my stats to see if I can figure out the problem. The things I'm most concerned or suspicious about are the O2 Sensors, long and short term fuel sensors, and engine advance. Anyone that could e-mail me a file or provide any info would be great. My email is SaiLaser446NOSPAM@aol.com just delete the NOSPAM...it's in there so automatic search engines can't find me and put me in their database. | ||
| Brad Russell (Bradnc) Member Username: Bradnc Post Number: 227 Registered: 03-2002 |
Could anyone just send me a file of theirs? It won't take more than two minutes to do... | ||
| J E Robison Service Co (Robisonservice) Member Username: Robisonservice Post Number: 79 Registered: 10-2002 |
Why don't you describe what's in your file that has you concerned . . . we use a different kind of tester here but I'm certainly familiar with what the readings should look like. John www.robisonservice.com | ||
| Brad Russell (Bradnc) Member Username: Bradnc Post Number: 232 Registered: 03-2002 |
Thanks for the help. I'm not sure what could be off...so I just wanted to compare my results with someone else's to see if any of my readings very greatly. The problem is that after the truck has run for a while and then gets to sit turned off for less than 5 minutes it will run extremely rich right when I start it up. It smells like rotten eggs. Any idea what it could be? | ||
| D. Chapman (1hank1) Member Username: 1hank1 Post Number: 146 Registered: 02-2003 |
Converters? | ||
| Brad Russell (Bradnc) Member Username: Bradnc Post Number: 234 Registered: 03-2002 |
Well I had the problem and thought it might be the converters, so the dealership replaced them under warranty. The problem continued the next day after the new cats, so I don't know what the deal is. | ||
| Craig J Davis (Craigjdavis) New Member Username: Craigjdavis Post Number: 9 Registered: 01-2003 |
Brad, I have a very similar problem with a '96. I have not gotten to the bottom of it yet, but am trying to figure it out. I think it is either a sensor which is causing the computer to send too much fuel, or an intermittent lack of spark. If you get any further info I would like to hear about it. I'll be sure to pass on anything that I find out. Good luck, Craig | ||
| Brad Russell (Bradnc) Member Username: Bradnc Post Number: 241 Registered: 03-2002 |
thanks. I have no idea if this is a legit possibility but I figured I might run premium gas for 3 or 4 tanks and see what happens. I know all my O2 sensors are functioning fine, as shown by the OBDII, so I don't know what else to check. A new SAE Master Mechanic is going to start working at our shop so I'm going to get him to take a look at it. | ||
| Craig J Davis (Craigjdavis) New Member Username: Craigjdavis Post Number: 10 Registered: 01-2003 |
Brad, I was tinkering around today and decided to read the shop manual. I think that the problem may be the fuel pressure regulator. The symptoms match the description in the book. Basically, the regulator opens to allow some fuel to flow back to the fuel tank when the engine is pulling more vacuum, i.e. high rpm's. The idea is that when it is pulling more vacuum, the pistons will pull fuel out of the injectors so if the pressure is high in the fuel rail, then the injectors will pump in too much fuel. The regulator opens to reduce pressure in the rail thus reducing the amount of fuel delivered. So, if the regulator is not opening, either because it is bad or the vacuum line is bad, then the engine will run rich at high rpm's eventually becoming flooded. I changed the vacuum line today and will give it a couple of days to see if that was the problem. If not, I'll change the regulator. FYI the regulator connects to the fuel rail behind and below the throttle mechanism, i.e. where the throttle cable attaches to the butterfly valve axle. The vacuum line runs from the regulator to the lower part of the air plenum. I'll keep you posted on the results. The initial test drive seemed to show improvement. Cheers, Craig | ||
| Craig J Davis (Craigjdavis) New Member Username: Craigjdavis Post Number: 11 Registered: 01-2003 |
By the way, there is no electrical connection to the fuel pressure regulator, so it will not set off a check engine light until the engine becomes flooded enough to cause a misfire or to cause a problem with an O2 sensor. | ||
| Rich Zellmer (Personalt) New Member Username: Personalt Post Number: 32 Registered: 11-2002 |
Craig, I think my problem sounds similar. If I drive along the highway at 50mph I can go great for miles. However when I come down a hill or someone cuts me off I run in to trouble. If I have to take my foot of the gas pedal the car starts to miss. I have to pull to the side and let the car idle to about 10 seconds. The idle will bounce back and forth a bunch of times and then return to normal. I can speed up the fix but putting it in neutral and tapping the gas. I am not sure if it is giving the engine to much fuel or not enough. But I think we might have the same issue. I orginally thought vechile speed sensor for mine but tht didnt help.. | ||
| Bill Howell (Billh13) New Member Username: Billh13 Post Number: 23 Registered: 03-2003 |
Craig, What book do you have? I need one of those. | ||
| Brad Russell (Bradnc) Member Username: Bradnc Post Number: 246 Registered: 03-2002 |
Craig, that sounds exactly like what would cause what I have. I hadn't thought about that yet. I'm definately gunna run a vaccum test on that hose and see what else I can do. thanks, brad | ||
| Craig J Davis (Craigjdavis) New Member Username: Craigjdavis Post Number: 12 Registered: 01-2003 |
Bill, I'm using the Land Rover Workshop Manual for Discovery 1995-1998. Near the beginning of the fuel system section there are descriptions of each component and what symptoms a failure would cause. Many of the components are sensors, and therefore cause the check engine light to come on if they fail. The rest are "mechanical" parts and don't turn the light on unless they affect one of the sensors. So far, changing the vacuum hose seems to be doing the trick. Cheers, Craig | ||
| Craig J Davis (Craigjdavis) New Member Username: Craigjdavis Post Number: 13 Registered: 01-2003 |
Problem is still there, so I guess I'll have to change the fuel pressure regulator. It's a lot more expensive than vacuum hose. |
