Help! "Check Engine" light blinks, engine runs rough

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Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Saturday, August 18, 2001 - 05:07 am: Edit

This just started happenning today. First, I noticed the engine was running rough, some vibration felt in the steering wheel. Then I noticed that when I punched the accelerator, the speed would instead drop down as the engine hesitated.

Then, the "Check Engine" light came on. Uh oh, I turned around and headed for home. On the way back, the "Check Engine" light was alternating between blinking and constant on. I had to go easy on the gas or else the engine would run really rough. I also noticed that the RPMs indicator (it's an automatic trans) kept bouncing all around.

Help, what's going on? And what can I do to fix this? How much is the repair (approx)?

My Disco is a 1997 SD7, with about 59K miles.

Thanks,

Scott

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Rob Davison (Pokerob) on Saturday, August 18, 2001 - 06:24 am: Edit

well the book says if the light blinks dont drive it. i would take that one step further and not even run the car at idle.

i would check all my fluids,,, especially the tranny. i think it has to be ht to check though.
so when that light came on i would have stoped it where i was at and jumped out and checked.

since your car is cooled off now
i would seek out someone with an OBDII unit that could check the fault codes and then go from there.

you may have to call the dealer and get it towed and get them to diagnose the problem if you dont have access to any diagnostic systems localy so this part may cost you a few hundred.

depending on what the dealer finds you can then decide if you want to tackle the job buy yourself/ with the help of this bbs or have them do it.

-rd

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Alex Schubow (Alex) on Saturday, August 18, 2001 - 07:57 am: Edit

A blinking check engine light indicates a serious misfire. According to LR, it will blink when enough raw fuel is going into the exhaust to burn out the cat(s).

Alex

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Saturday, August 18, 2001 - 09:16 am: Edit

Alex -- thanks. misfiring is what explains the hesitating acceleration and rpm fluctuations.

Any idea why this would be happening?

The dealer is about 7 miles from here. Do you think it's OK to drive it that distance?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Saturday, August 18, 2001 - 09:18 am: Edit

Rob -- thanks, I'll check the trans fluid. I haven't done this yet since I bought the Disco several months ago. Can you tell me where the dipstick is to check the trans fluid level?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Mike Rupp (Mike_Rupp) on Saturday, August 18, 2001 - 11:40 am: Edit

The trans fluid dipstick in on the passenger side of the engine near the firewall.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Saturday, August 18, 2001 - 12:39 pm: Edit

I just took a quick look under the hood. I'm not that savvy with engines, so bear with me..

Since it seems reasonable that the engine is misfiring, I decided to check the plug wires to see if one had popped loose.

Would a loose or disconnected plug wire cause the engine to misfire or raw fuel in the exhaust?

I went around to each one and it all seemed OK -- except one plug wire up on the distributor (cap?). The last wire on the driver side was so loose it was only holding on by the rubber boot.

I reconnected it and started the engine with high hopes -- nope the "Check Engine" light is still illuminated.

Should I take a chance and drive it around the block for a while and see if it clears? Or at least see if it starts blinking again?

Would a loose plug wire cause misfiring, and therefore raw fuel in the exhaust?

Any other suggestions or help would really be appreciated. Thanks.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Axel Haakonsen (Axel) on Saturday, August 18, 2001 - 12:51 pm: Edit

Yes, a loose plug wire could definitely cause a misfire. If the check engine light is no longer blinking, you probably found the culprit. It takes a few engine cycles, but the check engine light will eventually go out -if- you have indeed corrected the problem. How does the engine run now, though? Nice and smooth? If so, the loose wire was probably it.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Saturday, August 18, 2001 - 01:12 pm: Edit

OK -- I took it out for a spin. The engine was running much much smoother, and there seemed to be more acceleration power than I had before.

BUT, even after driving for about 3 miles, the "Check Engine" light was still illuminated. It wasn't blinking (good) but it was still lit.

Does it need to be reset somehow, or do I still have a problem?

btw, I noticed on the loose plug that the copper contact was not bright and shiny like the contact of the other plugs. I've got a feeling like that plug has always been loose or was barely making contact (explaining the hesitations at cruising speed I had on a road trip).

So, does the light need to be reset (and how), or do I still have a problem?

Thanks,
Scott

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Dave on Saturday, August 18, 2001 - 03:03 pm: Edit

The problem may be sticking exhaust valves you will notice it most at 60mph or greater when engine is under slight load(going up a grade). To verify install a vacuum gauge to engine and tape gauge to windshild and road test car if the needle fluctuates when the car starts to miss you know it's valves.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By wags2034 on Saturday, August 18, 2001 - 04:57 pm: Edit

a possiblility is the fuel pressure regulator. pn#etc8494g (from atlanitic brit) $109.95. symptoms of this part failing is loss of power, when you press gas pedal it bogs down as is it is flooding out, and raw fuel in the exhaust. if this is the culprit an oil change would be in order as well due to too much fuel getting injected and mixing in with the oil. I had this happen. replaced the part, did an oil change, and it was good as new. if replacing your plug wire restored your power, the check engine light may just need reset or needs to cycle 3 times. oh and it is "check engine" and not "service engine" correct? the "service engine" light usually comes on at about 52k. let me know... good luck!

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Saturday, August 18, 2001 - 05:14 pm: Edit

wags -- I just had an oil change last month. Yes, it's the amber "Check Engine" light, not the other.

About resetting the Check Engine light -- how do I do that?

Thanks,
Scott
97 SD7

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Saturday, August 18, 2001 - 05:18 pm: Edit

btw, one thing I noticed on the plug wire that I reconnected, is it looked like it was "burnt" or corroded, unlike the shiny finish on the other connectors.

It was such a loose connection that the electricity was probably arcing causing the burn marks on the connector.

Does this warrant replacing the entire plug wire set?

oh yeah, still need help with how to reset the Check Enginge light.

Thanks,
Scott
97 SD7

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Jose A Cabrera (Jcabrera) on Saturday, August 18, 2001 - 06:25 pm: Edit

Sorry to say I had the same problem on my 96 Disco (at just about 40K miles)... The problem "sticking exhaust valves". The dealership where I purchased it (used) agreed to take care of the problem. It appears it is an expensive repair. By the way it was Dimmitt Land Rover in Clearwater Florida, I can proudly say, Dimmitt is by far the beast dealership I ever dealt with, I had BMW and MBenz in the past and they were never as good as Dimmitt Land Rover...too bad I am 2800 miles from them now.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Moe on Saturday, August 18, 2001 - 06:30 pm: Edit

It sounds like you solved the problem and the if so the check engine light should go out with some magical number of cycles. Otherwise someone (like LR dealer) with OBDII system to reset.

You may as well pay the $ and buy new leads, plugs, filters etc unless you have already done the 60k service, otherwise you will back posting with a similar problem. Take Wag's adivice and change the oil too. If you have been running on 7 cylinders for most of the time, I'm sure the cats and the oil have taken a hiding

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Sunday, August 19, 2001 - 04:02 am: Edit

Thanks Moe. Nope, haven't had the 60K service done yet. I just replaced the air filter with a K&N. So I guess the only other filter I need to replace is the oil and the fuel (?).

Do you think the cat is toast? From the time the Check Engine light came on and was blinking until I got home, was probably about 4 miles.

Top of pagePrevious messageNext messageBottom of pageLink to this message   By john on Sunday, August 19, 2001 - 04:41 am: Edit

the light will go off after 4 hot/ cold ( engine temp )cycles if the problem is fixed

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Alex Schubow (Alex) on Sunday, August 19, 2001 - 05:15 am: Edit

The only way to tell if the cat is on the way out (if it was totally plugged your truck would be running like shit) is to hook it up to a diagnostic scanner. Dealer can do it, or any mech. with an OBD-II diagnostic scanner can do it for you if they know their way around the systems.

If you live in the Chicago area you can come by here and I can check it for you. N/c for all disco brothers!

Alex

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Sunday, August 19, 2001 - 05:33 am: Edit

Thanks for the offer Alex. I'm in Northern Virginia. Any Disco brothers with an OBDII machine out here around the Reston/Dulles airport area? (don't want to drive it too far, until it checks out OK)

Top of pagePrevious messageNext messageBottom of pageLink to this message   By Scott A. Keen (Scottkeen) on Sunday, August 19, 2001 - 06:01 am: Edit

btw, where is the OBD2 connector on a 97? Is it an "ISO" type connector?

Top of pagePrevious messageNext messageBottom of pageLink to this message   By gp (Garrett) on Monday, August 20, 2001 - 05:06 am: Edit

drivers side under the dash to the right of the steering column.


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