Aftermarket Cam idle woes

It’s been a while since I checked stock idle timing with the spout in but 10° sounds too low.

Also what was the solution to the initial crank only running on 4 cylinders?


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jetski247 said:
Sorry about that, daddy duties got in the way.

When I read t Moss's article about advancing the camshaft four degrees and he gained power throughout the entire rpm, I now can attest to that is the TRUTH!!! I gained power from idle all the way through the entire range with torque to back it up, on speed density........in fact, pulls harder and better than the custom ground, minus the punch. This cam compliments the lazy stock shift patterns programmed into the stock ECU much better this way but I'm sure gas mileage or longevity may suffer. Idles smooth like stock, doesn't die at a light, vacuum in gear is 18.5.
When I say punch 👊, upper rpm throttle response seems slower, the custom ground and MAF seemed to be/have the best throttle response so far but may just be how speed density is....?

only problem that I'm having now as I think I'm running out of fuel at about 4,200 RPM the engine just kind of stalls right at 4200 and sits there and kind of fluctuates up and down a couple hundred RPM so either my fuel pump isn't putting out enough fuel (which is 2 months old) like the sock is clogged or the fuel filter, but more than likely my pressure's dropping at wide open throttle or my parts just flow too much air, but I noticed it after I installed the one inch phenolic spacer on the Edelbrock upper lower even with the custom ground. I noticed it with the aftermarket Cam that it did the exact same thing all of the sudden at 4200 RPM the engine would just kind of stall. Not sure if a 1" TB spacer, 1" phenolic plenum spacer, on top of an already larger port Edelbrock upper/lower causes any kind of wot vacuum issues???🤔
Usually when something is clogged the truck will just fall on it's face at wot and run fine till about 2500rpm.

my baumannator was set to shift at around 4k and didn't notice it till I switched back to speed density, stock shift points are at 4500, which I can't get to, so now I have to rig a hose to be able watch pressure under load while I drive. Cuz at park/neutral checks fine, even revving.

also noticed my temp Guage is all over the place, if I roll the window up and down the needle goes up?? If I roll the window all the way up and keep the button down, the needle will climb all the way to max..........so, not sure whats going on with that. And a CEL popped up after 10 miles or so, which I lost my code reader so gotta jump the test connector.

So far so good, I'm happy with the performance so far, this is with stock 1.6 rockers, cobra 1.72's are on the bench.

Timing is set to 10 deg with spout out. Spout in shows 10 at idle as well. And I've got a awful loud belt squeal now...........new belt to, well less than a year old. Not sure if something got misaligned???? Idler pulley and tensioner are new.
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Take this from the king of over thinkers. YOU ARE WAAAAAAY OVERTHINKING THIS. Port sizes, cam timing, Tmoss...

I've asked before, but you really need to check your fuel pressure as that will tell volumes at WOT. A wideband wouldn't hurt either. Finally sounds like you have electric gremlins as well. So get all that mechanical stuff sorted before getting all theoretical :)
 
For any driveability problem, the first tool that touches the car is a fuel pressure gauge. If that's not right, nothing else will be. And the fuel system is the most neglected part of the car. A new fuel filter has probably cured more random problems than any other single part.
 
Well I'm an idiot................
1/4 tank of fuel wasn't enough, pulls so hard now that it was starving it of fuel I guess, or my gauge is getting stuck?? I filled it up and it shifts at 4500 now, which never was an issue before...........AND If you read my previous posts about the fuel system.......everything was either replaced or cleaned besides the lines.

And I DID check fuel pressure which was good.......but not while driving, my hose isnt long enough.......wait, that came out wrong.........

I know my posts are long but I just replaced the fuel pump fuel filter clean the injectors and new fuel sock about 2 months ago........
Seriously, all bs aside, truck is fun to drive again, tires were spinning at 1/4 throttle take offs (when turning) and hadn't did that since it had stock size maypop tires on it.

Throttle response is much improved, throughout the whole rpm range. Truck lifts off the ground from a 30mph stomp. Almost too much, I see why ford retarded it, it's just a little too snappy for the average Joe but has the power where you need it.

And if I can find out where where this loud belt screech is coming from I can listen for any Deto that may be going on

And just for thoughts, had I removed the plenum spacer, then drove normal to the gas station and filled it up, then floored it I would have seriously thought it was the plenum spacer..........lol
 
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Yes, besides the belt squealing and coolant gauge that acts like the charging gauge now. The more power I consume, the higher the gauge reads.......it's never done that before, and all I did was a cam swap.

And how does a belt go to never making any noise, to cam swap and squelch like hell? Literally 6 bolts hold All the accessories in the engine.........how?

I wish someone could drive this and compare it to a stock lightning ⚡, even with this huge sterling 10.5" massive rear end, I couldn't imagine my old lightweight 8.8, light rimmed, 5 lug axle.....
 
jetski247 said:
Yes, besides the belt squealing and coolant gauge that acts like the charging gauge now. The more power I consume, the higher the gauge reads.......it's never done that before, and all I did was a cam swap.

And how does a belt go to never making any noise, to cam swap and squelch like hell? Literally 6 bolts hold All the accessories in the engine.........how?

I wish someone could drive this and compare it to a stock lightning ⚡, even with this huge sterling 10.5" massive rear end, I couldn't imagine my old lightweight 8.8, light rimmed, 5 lug axle.....
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Did any oil or anti freeze get on the belt?
 
No, belt was the first thing removed after loosening the fan bolts but maybe a pulley? Either way I blasted it with brake cleaner while it was running. The only thing that shuts it up is lube, and it's only temporary. As the temperature outside gets warmer it shuts up. Pulleys all were replaced during first cam swap, well all but crank, AC, power steering.
 
Well if you blasted the belt with brake cleaner I'd replace it. While it's off spin stuff and listen for noise. Our trucks are notorious for eating the tensioner bolt so check that too.
 
I believe it was both at first


distributor was set to the number one as exactly was when removed, to the mark I made on the dist. base, on #1 cylinder at tdc, but since cam was advanced, timing was now off.................................. and I had to adj, which was way advanced I believe when i first checked it due to the cam advance. and spit out the intake several times when revving the engine.

so, initial timing was changed to 10*............as before, with the serpentine belt off, truck runs like crap but runs long enough to set timing before assembling everything else to find out you have to take everything off again because you forgot something. but yes, it backfired through the intake and throttle response sucks. its only running on the battery's power, which declines the longer it runs, so as battery weakens, so does spark, fuel pressure........you get the idea. weak battery = weak 12v electrical parts, it has been powering my work light for several days and was I guess slightly week, even though its a bad @$$ AGM

so, upon assembly, first several 15 second runs, timing was off, fuel pressure is now weak due to the battery and it backfired through the intake and was very hard to start. i believe it was lean due to low fuel pressure from low battery voltage, timing was advanced since camshaft moved and I guess the teeth on the dist. and cam were now slightly off from my mark? could have been human error on that one.

so i put the serpentine on, fully charged battery, timing was adjusted since dist was slightly off........so it fired right up, idled beautifully, fuel pressure (i think was @ 38 - 42?) i don't remember, idle voltage was 14.2v, timing was 10* with spout out, then @10 with spout in but i think advanced to like 14 or 16?, not sure cuz its been several days. didn't spit through the intake anymore, throttle response was, well........just like stock, never really noticed a difference except for a slight exhaust tone change.......

so then, everything checked out good in the driveway, time for a test drive.....................

my fuel gauge was and is getting stuck at 1/4 tank......so on hard acceleration, engine is starving of fuel. so in the driveway, which is level, fuel pressure is fine with a new fuel pump, new fuel filter, clean fuel lines, clean injectors and new FP regulator.............but not under WOT runs with a low tank, which was a new issue.

as I drove the truck, it wouldn't rev past 4k, next WOT run wouldn't rev past 3800 and kept dropping.......so went to the gas station, filled it up and truck shifts right where its suppose to on WOT runs........but my gauge, even though new, must be sticking somehow. luckily i cut a hole in my bed for easy removal/access with a nice and nifty little cover.

again, i think it was both.



today it finally showed an issue but had been running flawlessly.

on cold start, idle was @ 650, not the cold 1500ish high rpm for several seconds and slowly drop............... it just started at 650 and stayed at 650. took the kids to school, died when i got to the school. fuel was near ( you guessed it) 1/4 tank)........... so i putted to the gas station and it kept dyeing at idle but ran fine?????

so what i think is, my IAC is not working right or is getting stuck. truck runs strong, then let off throttle, as you get to a stop, rpm fluctuates up and down then dies........ even with a full tank.
 
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as an update, truck still spits and pops through the intake sometimes. usually when its cold but not every time. its completely random.
fuel pressure is good, i even swapped out a whole new fuel pump assembly just incase the cheap china pump was giving me issues, this one is a delphi. no check engine lights either.

symptoms:
idle will drop to about 500, if i give it about 1/4 throttle, it spits through the intake manifold.
if i give it 1/2 throttle or more, runs fine and strong, even at WOT.
let off the throttle, idle drops back to about 500 and will repeat for about 15-20 minutes then return to running fine.

possible causes:?
too much valve preload?
bad ground somewhere?
computer, its the original and has not had the capacitors replaced.
 
well....... yesterday i started going over all the wireing........ again...........you know, human error.
underneath the truck when checking pinion angle with my new angle finder since i have a strange 65mph vibration, i decided to look at the o2 sensor and wiring, i removed the sensor and found corrosion around/on one of the wires going to the sensor. it was so corroded that it was pushing the insulation of the wire away. so i replaced the sensor with a new bosch hego and so far so good. too many beach trips i guess. which makes me wonder why it didn't trigger the check engine light? its speed density with only one hego and not 2. im hoping thats what was causing the strange random spit and pops at 1/4 throttle.
 
The O2 sensor likely didn't trigger a code for a few reasons. First of all, OBDI computers aren't that smart. Unless something has gone completely tango uniform they typically don't notice. Second, if the corroded wire was for the heater it isn't even something that would be monitored. But that would explain why you have issues while cold more than when hot. The heater is what wakes up the O2 sensor in the morning and without it the sensor may not be working correctly for several minutes after a cold start even though it is expected to be providing closed loop feedback.
 
oilwell1415 said:
The O2 sensor likely didn't trigger a code for a few reasons. First of all, OBDI computers aren't that smart. Unless something has gone completely tango uniform they typically don't notice. Second, if the corroded wire was for the heater it isn't even something that would be monitored. But that would explain why you have issues while cold more than when hot. The heater is what wakes up the O2 sensor in the morning and without it the sensor may not be working correctly for several minutes after a cold start even though it is expected to be providing closed loop feedback.
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Amusing anecdote from YESTERDAY.... I'm driving to work in the morning, it was a bit chilly here in NC, and got a CEL. Couldn't detect any significant issues in drivability, maybe a slightly rougher idle. Driving home from work in the afternoon, no CEL. But no cruise control, either. Hmmmm...

Well, it seems I had borrowed the fuse from the O2 heater/cruise control slot in the underhood fuse box over the weekend to replace the fuse I'd blown after installing the fog lights, since it was the only available 15A fuse in the underhood box. I hadn't bothered to look up what fuse I was borrowing, and had neglected to replace it immediately.

So, no O2 heater, CEL in the cool morning, no CEL in the warmer afternoon. Keep in mind that this is a basically stock truck, so O2 correction would be minimal.
 
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lets say you unplug the o2 sensor, does the computer still use a base map to keep everything running?

it hasn't spit and popped through the intake since I replaced it, but may be coincidence since its random, but does seem to act up when its cold and only at idle to 1/3ish throttle when it happens.

its like its running lean and backfires through the intake, but what would make it run that lean besides fuel pump, which has been replaced 3 times since this write up.
 
FMOS Racing said:
Amusing anecdote from YESTERDAY.... I'm driving to work in the morning, it was a bit chilly here in NC, and got a CEL. Couldn't detect any significant issues in drivability, maybe a slightly rougher idle. Driving home from work in the afternoon, no CEL. But no cruise control, either. Hmmmm...

Well, it seems I had borrowed the fuse from the O2 heater/cruise control slot in the underhood fuse box over the weekend to replace the fuse I'd blown after installing the fog lights, since it was the only available 15A fuse in the underhood box. I hadn't bothered to look up what fuse I was borrowing, and had neglected to replace it immediately.

So, no O2 heater, CEL in the cool morning, no CEL in the warmer afternoon. Keep in mind that this is a basically stock truck, so O2 correction would be minimal.
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I get codes for my O2 sensor and PIP sensor all the time. No driveability issues at all, just the CEL and it usually goes off a few miles later. People have been spoiled by OBDII and don't remember how bad OBDI engine management systems are.
jetski247 said:
lets say you unplug the o2 sensor, does the computer still use a base map to keep everything running?

it hasn't spit and popped through the intake since I replaced it, but may be coincidence since its random, but does seem to act up when its cold and only at idle to 1/3ish throttle when it happens.

its like its running lean and backfires through the intake, but what would make it run that lean besides fuel pump, which has been replaced 3 times since this write up.
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It should run OK in open loop with the O2 sensor unplugged. The problem would occur if there was another sensor acting up. The IAT sensor is a good example. When they fail, they usually fail to a high temp. My mom's 96 Ranger had it fail and it always read 400 degrees. At that temp the density calculation on the air meant that it didn't inject much fuel and the truck was really hard to start. Once it was started the O2 sensor made the adjustment and it was fine. Without the O2 sensor it would have always run lean, and this is an OBDII vehicle that is much smarter than the OBDI vehicles that were built through 95. If you had both an O2 sensor issue and a temp sensor issue it could cause lean running until either the O2 sensor heated up and started working or the engine temp reached the temp sensor thought it was at.
 
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