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Old 05-26-2011, 09:56 AM   #1
enduro_man
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Thumbs up! Fixed it!

FIXED IT! THE NEW COIL WAS SHOT!

(Posting updates at end of thread)

I am still having issues with my 87... here is what it is doing.

Cold fires right up sounds great, runs great, smooth, etc.

gets up to factory temp 210-220 and she dies won't start.
Doesn't give any codes anymore.

Things I have tuned up, fixed, and checked along the way.

replaced fuel regulator diaphram (was leaking)
MAF is clean
New MAF relays
New fuel pump and filter
new coil, wires, plugs, module, cap, rotor
holds fuel pressure

I don't want to through parts at it... but I am not sure where to look next. I have heard people talk about the oil pressure sending unit causing problems... should I try that?

any help is greatly appreciated... I really want to drive!

Last edited by enduro_man; 05-29-2011 at 02:09 PM. Reason: FIXED! YAY
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Old 05-26-2011, 10:02 AM   #2
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I am going to have to do more checking... but the fuel pump may be cutting out at temp.
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Old 05-26-2011, 12:11 PM   #3
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Wire up an idiot light to see if the pump is getting power when it runs for a while. When it causes the problem also check on the fuel pressure. After that, check if you are cranking and getting a blue spark
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Holley Stealth Ram, 42# injectors, AFR 190 heads, 1.6 intake RR and 1.5 exhaust RR, 230/236 - 110 lobe sep, 108 intake centerline (2 deg. advanced), TPIS Long Tube Headers, Random Tech Cat, Borla exhaust, Rossler Trans, HiTech Motorsport tuned ECM.
 
Old 05-26-2011, 12:24 PM   #4
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always drop back to the basics of compression,
air flow in and exhaust out of the engine,
ignition spark, strength and timing,
and fuel delivery,volume and pressure
oil pressure and temp
cooling,temps and fluid levels (fuel,oil,coolant)
computer controls and sensors
obviously compressions ok, so that only leaves the remaining potential problems

Id check for fuel pressure is steady and spark is consistent first and verify the spark plug condition as clear pictures of the plugs numbered by cylinder can give a great deal of info
id check for vacuum leaks , and loose battery connections and loose grounds,the symptoms would make me think its ignition , sensor, CPU,or fuel related

http://forum.grumpysperformance.com/...hp?f=32&t=1401

http://forum.grumpysperformance.com/...php?f=80&t=728

http://forum.grumpysperformance.com/...php?f=70&t=202

http://forum.grumpysperformance.com/...php?f=32&t=168

http://forum.grumpysperformance.com/...php?f=32&t=596

http://forum.grumpysperformance.com/...8&p=7622#p7622

http://forum.grumpysperformance.com/...hp?f=32&t=3954
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IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
Old 05-26-2011, 12:38 PM   #5
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Found it... I think

Well everything is in order... pressure, spark, no codes...

However, it appears that the central Cat is toast super heating the exhaust... I am guessing that has toasted the o2 sensors as well. The engine is actually pushing exhaust out before the coupling into the cat...

I don't exactly know why that causes it to die when hot... Maybe someone can enlighten me.

Time to save some pennies for an exhaust system cat and back.
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Old 05-26-2011, 12:43 PM   #6
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Quote:
Originally Posted by enduro_man View Post
Well everything is in order... pressure, spark, no codes...

However, it appears that the central Cat is toast super heating the exhaust... I am guessing that has toasted the o2 sensors as well. The engine is actually pushing exhaust out before the coupling into the cat...

I don't exactly know why that causes it to die when hot... Maybe someone can enlighten me.

Time to save some pennies for an exhaust system cat and back.
If that is the case, drive it for a while with it dumping straight out the manifolds before the cats. If the problem goes away, it is the cats.
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Old 05-26-2011, 12:59 PM   #7
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if your running rich the cats tend to heat up, if your running EXTREMELY RICH the cats melt and clog, if the cats are partly melted thats more than likely allowing the engine to run untill heat expands the crud in the cats and chokes the engine, melted cats are a RESULT of a fuel control problem not the CAUSE, a bad fuel pressure regulator, or defective injectors or defective sensors can cause the problem, as always theres ways to TEST & VERIFY, before you go throwing money at the problem by buying /installing random parts
pulling trouble codes helps but its not the ONLY source of info

"the symptoms would make me think its ignition , sensor, CPU,or fuel related"
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IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
Old 05-26-2011, 01:46 PM   #8
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Never give up.

Again thank you for the help!

I have talked to a few local shops and the conclusion is that even if the cat are toast that they will not cause the engine to die @ temp.

I hate tossing random parts at the problem I am not sure what to do next other than take it in to a shop.

I have no doubt it is a "simple" problem I just haven't found it yet.

but I am persistent. I have built several carburated chevys and have work on many imports so I don't any problems wrenching...

I just am not sure what to do next... since it runs perfectly when cold.

I was thinking about throwing a oil switch at it since I have read of people having similar problems with it.

Thanks again!
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Old 05-26-2011, 02:03 PM   #9
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Quote:
Originally Posted by enduro_man View Post
I was thinking about throwing a oil switch at it since I have read of people having similar problems with it.
That was going to be my next suggestion. Should be simple to prove without buying anything. Let the engine warm up and "shutoff" then insert jumper on the low oil pressure fuel shutoff sensor plug and see if motor re-fires
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"If you're not on somebody's shit list, you're not doing anything worthwhile"
Old 05-26-2011, 02:12 PM   #10
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If it is the cats disconnecting them will help verify the problem. After which you can chase it down to the root cause
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Old 05-26-2011, 02:24 PM   #11
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More

I went back to the basics!

at 205 degrees the spark quits...

it has a new coil, module, cap, rotor...

could the capacitor cause this problem... I did not replace it yet....
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Old 05-26-2011, 02:42 PM   #12
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the capacitor housing is trashed oem broken apart... rusty... went through hell and back five times...
going to get a new one... let ya know how it turns out.
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Old 05-26-2011, 04:03 PM   #13
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still no spark... has power to the coil... uhhh. I feel like I am chasing my tail. I guess I can check the ground... or maybe the new coil or module is bad... but it is the same issue that grounded me to begin with.
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Old 05-26-2011, 07:51 PM   #14
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http://forum.grumpysperformance.com/...8&p=7622#p7622

http://forum.grumpysperformance.com/...hp?f=70&t=3797

http://forum.grumpysperformance.com/...hp?f=70&t=3301

http://forum.grumpysperformance.com/...lit=vats#p3403

http://forum.grumpysperformance.com/...php?f=70&t=270

might help
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IF YOU CAN,T SMOKE THE TIRES AT WILL,FROM A 60 MPH ROLLING START YOUR ENGINE NEEDS MORE WORK!!"!
IF YOU CAN , YOU NEED BETTER TIRES AND YOUR SUSPENSION NEEDS MORE WORK!!
Old 05-27-2011, 12:41 AM   #15
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Puzzled

In a good way I think... I have got her running hot or cold. But I am not totally sure the how or why of it... Spark, fuel, ..... all good and running strong... I am not holding my breath though.

It is probably because I made an appointment for the local pros to take a look at it.

all I can figure is I miss diagnosed the spark in the day light... sorta doubt it... but I have made one or two mistakes before.

The fuel system was / is dirty and I have been cleaning it with lucas injector cleaner... perhaps it was the major issue along with the other minor ones...



It has been a long strange trip. All I can do now it take it out and run it. And hope I don't have to call AAA.


Enduro is enduring...
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