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Bill K (Bill_K)
| | Posted on Saturday, October 19, 2002 - 07:05 pm: | 
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On a 95 disco, if car sits for more than 15 minutes, its hard to start. Engine turns over fast, but doesnt start. If I give it a little gas while its cranking, it'll start up. When it does, blue smoke with a gas smell comes out the tailpipe. Once started, it runs great. Do I have a bad fuel injector? Thanks. |
John Moore (Jmoore)
| | Posted on Saturday, October 19, 2002 - 08:13 pm: |
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I may be way out of line here, but on my 88RRC I have a cold start injector that puts a puff of gas in the plentium chamber to help with starting. I would think if it's an injector the problem would persist.
On my rig the cold start injector is on the back of the plentium chamber.
On the other hand, maybe your problem is ignition related. Since you smell gas after it cranks and has smoke, it sounds like there is excess gas in chamber not being ignited.
When was the last time you changed or checked your plugs?
I'm just guessing here...
John
88RRC |
Bill K (Bill_K)
| | Posted on Saturday, October 19, 2002 - 08:38 pm: |
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Thanks John. The plugs, cap and rotor are Bosch Plats, and the cap and rotor are oem. I changed them about 3 months ago. The problem just started today. Does a disco 3.9 have a cold start injector? |
John Moore (Jmoore)
| | Posted on Saturday, October 19, 2002 - 11:11 pm: |
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Again our rigs may be very different, I have a 88RRC with a 3.5 and your running a 4.0.
My cold start injector is located on the back of the plentium chamber and is controlled by a multi pin harness. (If the same try cleaning with contact cleaner) This harness is connected to the back of the fuel rail by small fuel hose in turn connected to a rather large valve. Check the hose. I was surprised by the flemsiness!
As general maintenance you could clean the injector contacts with contact cleaner. They are easy to disconnect. On mine you push in the small wires and pull up.
Hope this helps.
John
88RRC |
Bill K (Bill_K)
| | Posted on Monday, October 21, 2002 - 07:33 am: |
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This morning I turned the ignition to on-off four times in order to boost up the fuel pressure. The car started immediately. My fuel filter was replaced about a week before this problem started but I dont see any leakage around it. My fuel pump was replaced about 9 months ago so I dont think thats the problem. Car idles and runs good. My guess is fuel injectors. I think someplace on the web sells them for $60 each. can someone give me directions on how to go about changing them? |
John Moore (Jmoore)
| | Posted on Monday, October 21, 2002 - 10:51 am: |
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You have to may have to remove the plentium chanber and definitely the fuel rail. I found them difficult to get to seat properly, and I had the manifold out! Use lots of silicone.
You can get yours reconditioned and matched for about $40 each. Where are your located? Here in the NE www.robisonservice.com can do it for you. I was able to buy reconditioned ones a NAPA for $59. I broke one when rebuilding the top of my engine.
That's some good dough for something your not yet sure is the problem. Maybe you should have someone check it out with a scanner.
Silly question, but is the fuel filter going in the right direction? I also cracked a rusty fuel line when I replaced my filter, maybe you have leak somewhere that was caused when you replaced the filter and not getting enough pressure.
-John
88RRC |
Bill K (Bill_K)
| | Posted on Monday, October 21, 2002 - 11:42 am: |
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John, the filter is in the right direction. The last shop to install the filter put it in backwards and I ran it for about 6 months like that until I changed it recently. I think I will try replacing the coolant temperature sensor first, as that is a $15 part. |
Mike Rupp (Mike_Rupp)
| | Posted on Monday, October 21, 2002 - 12:13 pm: |
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Bill: do you have access to a fuel pressure gauge? Even though you replaced the pump 9 months ago, what you mention indicates it might be a pump problem. (" This morning I turned the ignition to on-off four times in order to boost up the fuel pressure")
My '97 had the exact same situation: cycle the ignition to turn the pump on/off to build pressure & then it starts fine.
If the fuel pump is ok, it should build 34-37 psi with one turn of the key with the engine not running. |
Bill K (Bill_K)
| | Posted on Monday, October 21, 2002 - 01:36 pm: |
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Mike, assuming the fuel pump is ok and the injector is bad, wouldnt the fuel pressure be low? On the other hand, if the fuel pump was bad and the injectors were good, the fuel pressure would also be low. Right?
Since the Disco runs great, I may assume: A leaky fuel injector wouldnt be noticable while driving on the highway as a bad fuel pump would cause stuttering at high RPM's.
But could it be a bad coolant temp. sensor?
You have a point about the fuel pressure gauge and I will buy one today after work. Thanks. |
Mike Rupp (Mike_Rupp)
| | Posted on Monday, October 21, 2002 - 01:55 pm: |
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Bill: Pump bad, injectors good--> low pressure.
Pump good, injector(s) bad--> not necessarily low pressure.
When I had the bad pump, the only symptoms my car had was the occasional hard starting when cold. Even when the pump was ready to completely die, it still performed well at high rpm. I thought at first my problem was a leaky injector, but it was definitely the pump. |
Bill K (Bill_K)
| | Posted on Monday, October 21, 2002 - 07:14 pm: |
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Mike, I bought a fuel pressure gauge on my way home from work tonight and tested the pressure. Unfortunately it's dark outside so I didnt spend too much time on it.
With the engine hot, off, and ignition on, it read 38psi.
While idling hot, it read 30psi.
How does that sound? |
Mike Rupp (Mike_Rupp)
| | Posted on Monday, October 21, 2002 - 10:08 pm: |
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That sounds good. Also do this: make sure that there is no pressure in the system and then turn on the ignition. If you're at 38 psi still, I'm guessing that the pump is fine. I'd think the next step would be to check the injectors.
Also, with the gauge still attached check to see if there is any drop in pressure when you turn the engine off. If the pressure drops rapidly it could mean a leaky injector. |
Bill K (Bill_K)
| | Posted on Tuesday, October 22, 2002 - 07:40 am: |
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Could it be the fuel pressure regulator? I thought 30psi while running, is too low? |
Mike Rupp (Mike_Rupp)
| | Posted on Tuesday, October 22, 2002 - 08:20 am: |
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The LR book says 34-37 ignition on, engine off & 30psi engine on so the regulator appears to be fine. |
Bill K (Bill_K)
| | Posted on Tuesday, October 22, 2002 - 09:51 am: |
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My boss tells me some cars have a "cold start injector" which puts out a shot of gas into the manifold to help start the car. It knows the car is cold because it gets the signal from the coolant temp. sensor. I'll change the sensor, if that doesnt work, I'll (sigh) admit defeat and take it in to a shop. I've read too many things about people spending a load of $ on replacing parts without fixing the problem, since I'm saving up for a "toy", I have to be economical about this. |
Paul T. Schram (Paulschram)
| | Posted on Tuesday, October 22, 2002 - 11:12 am: |
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Bill:
Your Rover does not have a cold start injector, it handles cold starts through firmware control of injectors.
Before admitting defeat, try two more things for me. First, have you cleaned your Idle Air Control Valve? Secondly, although it sounds like it doesn't work, try running a few cans of injector cleaner through your fuel tank. I had the exact same symptoms and solved them either by these steps, or something I accidentally did while doing those steps.
FWIW I now use a can of injector cleaner at almost every fuel stop.
By chance does the diagnostic display have any information?
Peace,
Paul |
Bill K (Bill_K)
| | Posted on Tuesday, October 22, 2002 - 12:01 pm: |
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Paul, thanks for the advice. I cleaned the Stepper motor about less than a year ago, since I had an erratic idle problem (cleaning the stepper fixed the problem). Since then, I've only been running 93 octane, highway driving, so I assume it's still clean. I also ran a whole bottle of redline fuel system cleaner to a full tank of gas in the rover a couple months ago. I'll hook up the pressure guage to the fuel rail tonight and let it sit for a half hour or so and see what that leads to. Thanks again for the suggestions.
By the way, Mike, what manual did you read those numbers out of? I have the LR manual and it doesnt say very much except between 2.3 bar and something else (forgot) and the Haynes manual (or is it Chilton? the one with the blue cover) doesnt say too much either. |
Mike Rupp (Mike_Rupp)
| | Posted on Tuesday, October 22, 2002 - 04:57 pm: |
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Bill:
I got the values from the LR manual:
"Expected reading 2,39-2,672 kgf/cm2"
Doing the conversions gives results of 34.6psi-38.7psi.
Also:"Pressure drop-max 0.7 kgf/cm2 in one minute" (10 psi) If everything is fine, you'll probably see much less than a 10psi drop in a minute.
When the manual refers to 2.3-2.5 bar it is refering to the pressure when the engine is running (~30psi)
The whole reason that I suspected the fuel pump was when you said that when you cycled the ignition 4 times, the car started fine. This leads me to believe that each successive cycle allowed a weak pump to build more pressure.
Also, I'd at least do what Paul says: rechecking the stepper motor and maybe trying a different brand of injector cleaner. I used the Lucas brand available through Napa. It supposedly has a different ingredient than most (could be marketing hype), but that is a lot less expensive and less time consuming alternative to taking the injectors out.
By the way, the manual also says if pressure isn't correct after first checking the pump & filter, the pressure regulator might be bad. |
Bill K (Bill_K)
| | Posted on Tuesday, October 22, 2002 - 08:03 pm: |
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Mike, I just found in my LR manual that the pressure should be a min. of 34 psi. Maybe my pump needs replacing. As for the Pep boys fuel gauge, upon using it the second time (today), an o-ring shredded, causing the needle in the gauge to press my schraeder valve needle all the way in. When I removed the guage, I got a nice spray of fuel all over me and the engine. I had to take the schraeder valve out and repair it. Pep boys didnt have another guage for an exchange, meaning I paid $50 to use this stupid thing two times. I've had it. I dont have the time to tinker too much with this. I'm taking it in to a shop. Thanks for the help, though. |
Mike Rupp (Mike_Rupp)
| | Posted on Wednesday, October 23, 2002 - 08:52 am: |
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Please post the outcome. |
Bill K (Bill_K)
| | Posted on Wednesday, October 23, 2002 - 10:30 am: |
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I sure will Mike. I'm taking it in tomorrow morning. |
guru prasad (Simguru)
| | Posted on Thursday, October 24, 2002 - 07:58 pm: |
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Hello all....I have a vy deteriorated starting problem.....Things improved for a while with fuel addons and changing the ignition connection from spade to eyelet terminals...and I add BG44 stuff in the gas tank because I suddenly starting loosing power and heard knocking.....The Bg44k solved that problem but the starting worsened....I have to really crank 7-8 times and also pump gas.....I dont know if the injector is blocked or leaking ??
This happens at cold & hot....Someone mentioned changing coolant sensor.....Could someone tell me which one ? AMR1425 Transmitter Temp sensor or PRC3505 Switch Temp. ? one is small and the other is large and both are located near the thrmostat......I have a 95 Dis. 3.9
Thanks.... |
jeff
| | Posted on Friday, October 25, 2002 - 09:13 pm: |
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I had a hard starting 97 disco 4.0 with 73,000 miles. I replaced fuel pump, fuel filter, and finally tested with fuel pressure gauge. Read 35psi initially and dropped to 10psi within 5 minutes. Finally removed all roadblocks to the fuel rail and pryed it out. Propped it up and cycled the fuel pump. Well......several injectors were drippin' like a baby in a three day old diaper(sorry, tried to add some humor in this hard luck Rover story). Paid around $500 for (8) new ones from Atlantic British. Installation took a few hours, but know she runs like a.... Rover. My guess is that the previous owner used low grade gas causing buildup. |
redneck
| | Posted on Saturday, October 26, 2002 - 04:39 am: |
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Have you Checked the ignition timing? I had this prob and reset timing and it starts first time now. |
Bill K (Bill_K)
| | Posted on Saturday, October 26, 2002 - 09:01 pm: |
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Turns out to be leaking injectors. A set of 8 from Atlantic British will set me back $550. I'll find out next week how many were dripping. |
John Moore (Jmoore)
| | Posted on Sunday, October 27, 2002 - 12:12 am: |
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Before you buy new, check out rebuilding yours. It can be done for about $40 per injector. Save some bucks.
-John |
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