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With the spout plugged in, it appears the timing is advancing properly. The most important thing you can do after checking the timing is scanning for codes. Without that you are working blindfolded. How many miles on your truck? Also, when did the detonation start? Double check you timing, color the timing marks with a piece of chalk and try to get directly over the pointer. You should be able to run 12° without any detonation. I run 14° but on premium fuel.
With you recently performing a tune-up, check for correct part # and heat range on the spark plugs. You have a firing order is 15426378. If plug wires #7 & 8 or #2 & 4 are routed next to each other at the wire separator brackets or laying next to each other, an induction crossfire can occur which can cause an ignition miss, spark knock, buck/jerk, surge, or worse. I've even seen a #8 piston destroyed by detonation recently after a tune up because the #7 & 8 plug wires were routed next to each other.
A few issues such as EGR system malfunction, faulty knock sensor/circuit, lean air/fuel mixture (vacuum leak, dirty injectors, etc.), incorrect timing, engine overheating, carbon deposits in combustion chamber, etc. can cause detonation.
The most important thing you can do is scan the truck for codes and double check timing. Also, it wouldn't hurt to perform an induction system cleaning and add a good quality fuel system cleaner in the tank.
With the spout plugged in, it appears the timing is advancing properly. The most important thing you can do after checking the timing is scanning for codes. Without that you are working blindfolded. How many miles on your truck? Also, when did the detonation start? Double check you timing, color the timing marks with a piece of chalk and try to get directly over the pointer. You should be able to run 12° without any detonation. I run 14° but on premium fuel.
With you recently performing a tune-up, check for correct part # and heat range on the spark plugs. You have a firing order is 15426378. If plug wires #7 & 8 or #2 & 4 are routed next to each other at the wire separator brackets or laying next to each other, an induction crossfire can occur which can cause an ignition miss, spark knock, buck/jerk, surge, or worse. I've even seen a #8 piston destroyed by detonation recently after a tune up because the #7 & 8 plug wires were routed next to each other.
A few issues such as EGR system malfunction, faulty knock sensor/circuit, lean air/fuel mixture (vacuum leak, dirty injectors, etc.), incorrect timing, engine overheating, carbon deposits in combustion chamber, etc. can cause detonation.
The most important thing you can do is scan the truck for codes and double check timing. Also, it wouldn't hurt to perform an induction system cleaning and add a good quality fuel system cleaner in the tank.
Detonation started after distributor replacement. I've never had this problem before. I run 87 octane. I've heard about the plug wire induction crossfire issue and I've addressed that. I have also ran a few bottles of injector cleaner through the fuel system after I purchased it. I'll pull codes to see if there are any.
At this point I've adjusted timing 3 times, and it's at 8 degrees according to my timing light, which I don't trust. It has a **** that you set to whatever timing you want and then you dial it in to 0 degrees on the balancer, and supposidly that's supposed to be how it works. But if you just check the timing with the dial at 0, the balancer will read almost 11 when i set it to 8. I think I'm either not using it correctly or there is something wrong with it. I'm thinking about returning it and getting a different one.
If you read this PDF, look at page 8. The pictures at the top describe what I'm talking about. If I set timing normally, Fig. 7 will read 10 degrees as depicted. But on fig. 8 where they have the **** at 10 degrees and the balancer reads 0, if I do that with my light, I have to set the **** to 12 in order to read 0.
That says pre emission controlled and vacuum and centrifugal advance which you don't have.
I didn't read the whole PDF but it appeared at a glance that that advance **** thing is useless to you.
You'll have to read a little closer maybe, but I'd assume you just leave it at 0 and set your timing.
Just a thought since you're having issues - you do have the right distributor gear on the new distributor ? Matches the old one ? Cast is for flat tappet, fully machined is for roller cam. I think 93's should all have the roller setup, if I remember it right, Just graspin' at straws there, in case nothing else works.
With that timing light, you set the advance degrees **** to 0°, pull out the spout connector and turn distributor until the timing pointer is on the 10° BTDC. That's it.
With the spout plugged in, it appears the timing is advancing properly. The most important thing you can do after checking the timing is scanning for codes. Without that you are working blindfolded. How many miles on your truck? Also, when did the detonation start? Double check you timing, color the timing marks with a piece of chalk and try to get directly over the pointer. You should be able to run 12° without any detonation. I run 14° but on premium fuel.
With you recently performing a tune-up, check for correct part # and heat range on the spark plugs. You have a firing order is 15426378. If plug wires #7 & 8 or #2 & 4 are routed next to each other at the wire separator brackets or laying next to each other, an induction crossfire can occur which can cause an ignition miss, spark knock, buck/jerk, surge, or worse. I've even seen a #8 piston destroyed by detonation recently after a tune up because the #7 & 8 plug wires were routed next to each other.
A few issues such as EGR system malfunction, faulty knock sensor/circuit, lean air/fuel mixture (vacuum leak, dirty injectors, etc.), incorrect timing, engine overheating, carbon deposits in combustion chamber, etc. can cause detonation.
The most important thing you can do is scan the truck for codes and double check timing. Also, it wouldn't hurt to perform an induction system cleaning and add a good quality fuel system cleaner in the tank.
Originally Posted by Chris_1
That says pre emission controlled and vacuum and centrifugal advance which you don't have.
I didn't read the whole PDF but it appeared at a glance that that advance **** thing is useless to you.
You'll have to read a little closer maybe, but I'd assume you just leave it at 0 and set your timing.
Just a thought since you're having issues - you do have the right distributor gear on the new distributor ? Matches the old one ? Cast is for flat tappet, fully machined is for roller cam. I think 93's should all have the roller setup, if I remember it right, Just graspin' at straws there, in case nothing else
works.
That timing light is an older version of the one I have. The operation principle should be the same. According to the case on the one I purchased, it should read centrifugal, vacuum, and computer controlled advance. Regardless, it should be consistent between each way of measuring.
As far as distributor gear, I didn't even think to check. I just bought the distributor that Oreillys had listed for my 92 f150. I assumed it was correct but I don't see anywhere on their site that says what gear it has. http://www.oreillyauto.com/site/c/de...rd=distributor
Originally Posted by cts2433
With that timing light, you set the advance degrees **** to 0°, pull out the spout connector and turn distributor until the timing pointer is on the 10° BTDC. That's it.
I originally set it with the **** at 0 degrees, but I couldn't even tip into the throttle while driving without detonation. Then I checked the timing by turning the know, and it indicated closer to 13 degrees. So I used the **** to bump it down to 10, then had to go to about 8 and now I don't have any detonation. I thought I heard a little bit at 45 in O/D with heavy throttle, just enough without it downshifting, just barely but it seems to have gone away, or I was just hearing exhaust noise. I'm thinking about returning this light and getting a different style to compare to.
I drove it for the first time today after letting it sit all night and all day, and it starts easy, cruises really well, but if it's in 3rd gear and i'm driving 25-30mph or 4th gear at 40 mph, when I give it just moderate throttle it stumbles and doesn't want to accelerate. Doesn't seem to want to stall, just doesn't want to rev up and jerks. If I turn O/D off while at 40mph, I can give it a lot of throttle and it'll accelerate just fine. I noticed it most once it got to operating temp. I forgot to mention yesterday that I found the coolant temp sensor to be bad. The plastic connector spins where it attaches to the brass fitting. I replaced it a few months ago with a new sensor but it seems to have been defective so I got a new sensor under warranty and I'm going to try to install it tomorrow along with a new MAP and knock sensor. And then pull codes.
On a side note, I don't know if this is related or not, but when I drove it tonight there is a squeak that I've been chasing for a while and been unable to locate that doesn't sound like it's coming from the accessory drive. I haven't removed the belt to try and isolate it, but if I had to guess, I could swear it sounds like it's coming from the intake area of the engine which makes no sense (Could a distributor gear cause a squeak like this? video below). It's much worse under load. Like I said I've been chasing it for a while (few months), but I could never get it to squeak while I was trying to isolate where it was coming from. Today however, it has all of a sudden gotten much worse. Its dark outside, otherwise I would have pulled the belt and started it to see if it's accessory or not. I sure hope it is because it sounds really bad and I'm unaware of anything else on a motor that could make a squeak like this. Tomorrow I'll try to locate it. Heres a video of the squeak (click on the picture)
Yes, you need to return that light and pick up a cheap one at O'Reillys. My Snap On timing light died after 23 years of use. I was unwilling to spend that kind of money on another one so I bought a basic one from O'Reillys (behind the counter) for about 40 dollars.
As for as your squeak is concerned, it sounds like you have a dry/worn distributor bushing. This squeak is also a common concern on the Ford 3.0L Vulcan and the 4.0L OHV but it's a cam synchronizer that's in place of the distributor. With the truck is squeaking, grasp the distributor by the upper housing and cap area and apply lateral pressure to it and see if the squeak changes. If so, then replace it. Also it would be a good idea to inspect the cam gear. Just a recommendation, but it would be a good idea to soak the distributor in oil before Installation.
As for as the gear is concerned, you are fine there. Ford began using the 302 roller block in 1988 in the F series, however, they were still equipped with flat-tappet non-roller cams and lifters through 1991. 1992 on were all equipped with roller valve train.
This listing is for a '91 F150 - note that a steel or cast gear is available (distributor mounted TFI)
This listing is for 1992-1996 with a steel gear (remote TFI)
I installed the new MAP sensor and Coolant temp sensor and took it for a drive. Still has the stumble in 4th at 40mph under light throttle. I got a $40 dollar timing light from Oreillys and compared it to the other one. It reads 8 degrees base timing as well. So I'm going to return the one with the **** and keep the cheaper one. I ran out of day light this evening so I'm going to try and work on it some more tomorrow after work and try to re-route the plug wires one more time to see if that resolves the stumble.
As far as the squeak goes, I could not get it to squeak today! I don't know whats going on. It will NEVER squeak when I have time to try and locat the source. It's beginning to try my patients.
Just as a recap of what has been replaced and current symptoms:
-ECT sensor
-MAP sensor
-Entire new distributor assembly
-Spark plugs (2000 miles ago)
-Plug wires II
-Ignition Coil
-Base timing set to 8 degrees with spout disconnected
-Has stumble/minor detonation in high gears at low speeds with low/moderate throttle input.
-Starts and idles much smoother than it ever has
03-05-2016, 10:18 PM
