Engine Engine stalls after running 10 minuter

rockyracoon

Active Member
Nov 23, 2005
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margate NJ
I. Previously did an HCI swap and been having issues with lower intake sealing, after replacing the gaskets the third time I think it is now sealing. So anyway after running the engine approx 10 minutes the car will stall out. Im getting DTCs 122,332 and 542. The tps voltage is 1.26. The motor shakes a bit but stays running until around 10 minutes. The cam is a trick flow stage 1 and I do not have a tune yet. It seems to run pretty good until it falls on its face after ten minutes. Cylinder balance gives a 90. Fuel psi is good and vacuum is around 15 at idle.
 
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08GT500

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Jul 12, 2018
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Hi,
Running FelPro 1250’s?
Cyl balance test is OK.
Codes point to a fuel system issue. Vapor locking. Have a gauge to plug on the rail’s Schrader valve to measure fuel pressure?
Pull a few plugs & read the electrodes via color.
Have you checked your vacuum line’s routing when you reassembled?
Check for cross contamination of coolant in oil, it may also partially burn off, I.e, sweet smell from exhaust.
Engine temp staying stable?
Start the car with the radiator cap off & look for bubbles indicating a combustion to coolant passage leak path.
Is your PCV system functioning properly?
Are you running the correct PCV valve?
May be normal or greater than normal amounts of combustion gases escaping from a head gasket or similar path ending up in the crankcase that your PCV simply cant keep up with, pressure taking out gaskets or gases diluting the required 02 levels, causing it to stall.
TPS should be <1 volt @ idle.
A TF s1 Cam should be able to run relatively stable without a tune.
See if any of these line up for you.
-John
 

rockyracoon

Active Member
Nov 23, 2005
820
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margate NJ
John,
fuel pressure checks out ok... 39 at idle 41 with vac line removed. On my latest round of pulling codes it came up with only thermactor system codes since I don't have the crossover connected, I am still running the line going to the exhaust though. The TPS oor voltage code is gone after I removed and reinstalled it.

Running 1262s gaskets

I have replaced most of the vacuum lines and have been over them numerous times

I'm only filling the coolant system with water (temporarily) in case coolant could be getting into the cylinders so if coolant is in fact getting into the combustion chambers I probably wouldn't notice any sweet smell. I will remove the radiator cap and look for any bubbles.

The PCV was original equipment and seems to be functioning fine.

Head gaskets are new and using head bolt studs and nuts.

The GT-40 lower does have moderate pitting around the front coolant ports

I'd love to have a wideband setup right about now in an effort to confirm your suspicions.

Thank you much.
 
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08GT500

Active Member
Jul 12, 2018
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Massachusetts
Hi,
Funny, was just typing to you, lol
What year is your Pony?
Need a HC test to confirm combustion is source, but consistent bubbles, that’s something.
I do a fair amount of H/C/I swaps, tuning. Most H/C/I swaps aren’t overly complicated & it’s common errors that snag us.
Were the heads checked for flat (</=0.007/Ft), shop prep the heads & do a pressure test?
Very good, located bubbles & doing a leakdown. Good start.
If you lost an intake gasket(s) due to surface irregularities, e.g: leak, a few times, get a little aggravated, overtorquing intake bolts can peel a head up enough to cause a head gasket leak..
Any other smog removed during this GT40 swap/Cam swap, or was it only the Thermactor pipes?
-John
Using RTV around the coolant ports? A little bit will get you past minor surface irregularities...then another bead after that setup around the coolant ports. Happen to take any pics of the intakes coolant passage area irregularities for a look see?
 
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rockyracoon

Active Member
Nov 23, 2005
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margate NJ
Monkeybutt……. yes the car was jacked up and there were only a few bigger bubbles as opposed to a ton of smaller ones.

08GT500...…. My pony is a 95 vert. Yeah I should get the H/C kit
Heads were brand new
Finished the leakdown and all cylinders at or under 10% most under5% and all the leak was going past the rings, however keep in mind that the motor was cold.
Just the crossover pipe was removed (no thermactor passages) everything else is intact.
normal pitting around the coolant passages. I had the upper and lower to an automotive machine shop over in Collingdale PA today (The engine shop) Carl and his dad (also carl) that own the shop are great guys by the way. They said everything looked fine and even put a straight edge on it for me.
The last go around, I did not use any RTV around the cooling ports. So are you saying to put a bead around the cooling ports on the head and also on the lower around the ports ?
No pics of the ports but I will and post them to this thread.
I still am convinced (all things considered) that my issue is either a leaking intake in the lifter valley or coolant getting into the combustion chamber via the intake causing the rough idle and backfiring in the intake. If I had antifreeze instead of water in the system it would probably be easier to tell by looking for smoke out of the tailpipes but until I get this resolved I don't want glycol in the system.
Thanks so much fellas.
 
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08GT500

Active Member
Jul 12, 2018
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Hi,
Very good. I agree with your thought on what’s occurring, I’ll detail why. Good precautionary, avoiding Ethylene Glycol’s devastating affects on your bearings.:nice:
INTAKE INSTALL ONLY:
On SBF/BBF motor’s, early SBC’s, in addition to using (2) small topside gasket dab(s) of Hi Tack-one in front, one in the rear so gaskets don’t shift, I’ll use a continuous bead of permatex on both sides of 1262’s gasket’s coolant passages, (1) on the head side, (1) on the intake.
Additionally, I was suggesting a very light skim coat to cover up the moderate pitting you’d mentioned of the lower (Corrosion based-?) you previously described to/in addition to the beads around the lower intake to head coolant passages. between intake ports Now, method to avoid much of this...
HEADS INSTALL BEFORE INTAKE:
New heads. Before torquing the heads, you can grab all the intake bolts with the gasket(s) installed, intake bolts finger tight with an additional 5 Ft/lbs in proper sequence with a torque wrench minimizes head creep while they're being torqued down.
The real issue is the head locators doubling as Dowels.
OE’s (2) split pin’s leave quite a bit of slack for creep. The bolts taper up top to bring things in clos-er, studs are the best, but don’t have that same effect.
I’ll run these on most street motors, they really help. Full hollow pins, light taps with a soft hammer & they’re in.
https://www.summitracing.com/parts/tfs-51400420
After your (1st) torque pass of (3) head steps of torquing, back off the intake bolts will avoid interfering with your head torque numbers as little as possible can & do shift significantly, but not after your 1st pass.
Have learned over the years, the 1250’s work better for you than 1262’s.
Snip out the coolant passage crosscorner gasket section.
The Intake & head need be free of all old gasket material, debris, hospital clean surfaces and then torquing the lower needs to be done in the correct center- out crisscross sequence in stages. N.P., will post if you need it..
I’m pretty certain you don’t bother with the cork lower to block gaskets & use a good bead of Permatex. No idea why they even include them, lol.
The printoseal’s are good gaskets but certain (like 1262’s) are purposed as full Competition gaskets, suitable for a motor that’s Blueprinted, with frequent tear downs & higher accuracies.
Their surface area is slim, with a very square race motor they’re great with large port heads (note coverage around the coolant passages is small vs 1250 Gaskets). Not my choice unless I have a motor disassembled in the shop, and dead on alignment on between heads, block, intake is a breeze.
If I see error in a valuable intake, I’ll opt for a known square surface and a >/=32RMS finish value and mill 0.300 off each side and drop 0.25 intake spacers in both vs “making it work with Permatex”. I don’t much like that, to be clear, wrong approach, but things in the real world aren’t always so accurate, it works reliably, done neatly and Permatex remains pliable, shifting with engine’s heat cycles.
What head’s are you running, TrickFlow 170’s, AFR’s?
I hope this helps, not the first I’ve seen & causes lots of headaches.. Laying the intake down & bolting lightly to one head, light behind the motor & looking across it will help gauge things. The OE Ford steel core (Black) gaskets also work well, if lined up tight.
Good luck!
John

**I began drilling 289-460’s decks with (3) 3/8” holes, reaming +.0002 for dowels for a light press if an aftermarket block, protruding 3/16”, heads the same +0.011 over. I’ll only do the block’s holes on a Mill, but made a jig with Tungsten inserts & locators for aligning the holes in the heads with a W letter drill (0.386) to keep alignment tight. Also lines up to cut the required head gasket openings.
That works every time.
 

rockyracoon

Active Member
Nov 23, 2005
820
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margate NJ
Wow thanks for the great info John.
See attached pics.
BTW it took me 3 hours to get the heads clean in the attached photo. I had used the 3m weatherstrip adhesive, Big mistake, from now on ill just use the high tack or indian head.
In the photo of the manni gasket on the head youll notice that the gasket is not in the head gasket tab, If I locate the gasket in the tab there is only like 1/16" of gasket above the top of the intake ports. I use the right stuff on the china rails so I dont think moving the gasket will cause a sealing issue at the rails as im sure it squishes beyond the rail to the port and starboard.
Those gaskets are 9334s and not the ones I will use when I try again although
I do like the 9334s but the port openings are a tad narrow for my ports. I did find a ground strap off , its the one going from the frame to an exhaust manifold stud and also in regards to grounds I do not have one for hego ground in the injector harness like the older fox mustangs do. I will have to reference my EVTM catalog and find out why.
 

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rockyracoon

Active Member
Nov 23, 2005
820
23
39
margate NJ
well after 4 tries to seal the lower intake it appears I finally got it to seal. This time I adhered the gaskets to the lower intake with some high tack, I know that is not the way your supposed to do it but I figured it was worth a try. The car will stay running and the only think going on is a pretty good surge. Now I will try to troubleshoot the surging using the surging idle checklist but the backfiring in the intake is completely gone and the throttle response is great. Gotta change the oil now as im sure some water has gotten into the crankcase due to the 4 failed intake manifold installs. I really think that the surging can be corrected with a tune.

The only detraction of the successful intake install is the fact that I used some 9334 gaskets which have port openings a tad small for the ports in my heads but they fit over the gt-40 intake fine. BTW those gaskets were used on one of the previously failed attempts but were in good shape, not sure if they were compressed but they are working. I will probably get some 1250s gaskets down the road since I now have a method of installing the lower that works.
 

08GT500

Active Member
Jul 12, 2018
898
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Massachusetts
Rocky....
Hi, I apologize for not getting back to you sooner, some medical things came up.
This is what I see.
You’ve got a solid 95’ 5.0, cylinder balance test and leak-down both suggesting the Motor is healthy. I’m not privy to the oil pressure, I’m guessing it’s solid. (?).
Money spent into this, top end, Heads, TFS-1 Cam, lifters, R.Rockers, all the extra’s.
Pic’s helped greatly when posted.
Observation: Intake’s seal surface is in an advanced state of corrosion, degradation, pitting, deep file marks, with an earlier failed attempt to use a filler putty like Devcon, JB Weld, etc.. Visually, difficult to discern whether actual welding was attempted.
Those fillers work fine to hold parts in place, repair threads in a pinch, repairing correctly once possible, usage for repairs under stress within an engine is creating a time bomb. It blows under & that’s the end.
Little original surface area is now left for intake gasket crush for sealing reliability against 10-12 PSI of coolant pressure.
With everything going as they should for your setup right now, I’d suggest (at least) seeking out an alternative GT40/ GT40 Intake.
Chucking that intake & finding a decent one for 100$, bolt it up & never looking back would end speculation. Gasket pic’s below on TF heads, fit GT40’s similar.
Glad to hear it’s running better, I’d had no doubt the combo is solid. Just no clue the intake was that severe. Not much margin left for a gasket.. Only putting in my .02, it’s got great potential, of course you want it to remain reliable.
Talk soon..Good luck!
-John

438093B2-7A5E-4BB1-AE0C-CBD839C60E58.jpeg

So, going across that intake’s flange..there’s major pitting, (Heavy) file marks, and remnants of the filler(Blk. Arrows).
922D2D79-F6FB-4E57-A573-8FF66DC8256A.jpeg
GT40P, reasonable surface.
CE47EFD9-D69B-4662-839F-968A7A3577DC.jpeg
Mock: Felpro 1250’s on left, Ford black graphite gaskets on the right; as viewed. TrickFlow T.W. 170cc hand polished ports.
 
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