1975 Triumph Spitfire with Silvertop won't start !

[gregsterling0000@aol.com]

1975 Triumph Spitfire with 20v Silvertop AE101 from 1996 Corolla, AFM, stock ECU. Ran great spring, summer, fall. That is till some dumb ass decided not to let well enough alone and went to a .8mm head gasket for higher compression and the lighter blacktop flywheel, new VVT. All back together now, but won't start! Has spark, has fuel injector pulsing, has fuel pump. Dimples on cams match at 3 o'clock and 9 o'clock with witness marks at 12 on both and cam at TDC. #1 is in firing position on distributor. Timing light indicates a range of about 15 before to 0 when distributor is adjusted thru it's range. Not even a cough, although once or twice I thought it might have fired for a second.

Initially was showing code 21 (intake air sensor) and code 31 (vacuum sensor). Showed code 12 after cranking with injector disconnected to test it. Currently not showing any codes. ECU was reviewed, no leaking caps or burned traces. All ground wires are connected on engine, frame.

Questions:

- does AFM have intake air sensor built in or does it need a separate sensor? If separate, is it possible that not having one in combination with higher compression would cause engine not to start? Not having one was never an issue previously.
- are codes meaningful/accurate on engine that only cold cranks, does not start?
- is code 31 actually relating to AFM, not vacuum sensor? Thought only BT's had vacuum sensor.

Would greatly appreciate any help or random thoughts.

[jondee86]

Have you pulled a plug after cranking to see if the plugs are getting wet with fuel ?

Cheers... jondee86

[BattleGarage_RS]

Hi Greg,

I was going to reply to your email, but I will just respond here since I found you.

If you are getting spark and are getting fuel, that's more than half of the battle.

I think those error codes are pointing at the AFM connection. The AFM has a built in intake air temperature sensor - it has to for the fuel injection system to properly calculate air density.

I'm guessing you have tried cranking at different throttle openings? That sometimes helps me figure out if I am too rich or too lean to have a proper start off. Pull your plugs, they should be wet with fuel. If they are not, then you actually aren't getting enough fuel when cranking. My thoughts are that the wiring to the AFM have become intermittent or damaged since the PO removed the head. I would start ohming out back to the ECU to make sure you have continuity. I would also make SURE all grounds are attached to the right places on the block, and make sure they are not damaged. Not having a proper ground will definitely keep things from moving forward.

Good luck,
Grant

[gregsterling0000@aol.com]

Thanks to all. Will do some more investigating this weekend. A bit cold out right now, about 24 degrees, not real conducive to working in my unheated garage!
I did not pull plugs after cranking, will look into that this weekend. I did remove air box while leaving AFM connected and with flap held open slightly and opened butterflies on throttle bodies to spray in some starting fluid in hopes of seeing some signs of life. No response, but for all I know it may have been flooded at that point from prior attempts.
All the same grounds as I had on the car previously have been re-connected, but I will re-check all grounds, possible air leaks, and such this weekend and report back.
Do I need to pull plugs on all sensors prior to checking continuity of wires from AFM plug to ECU plug? Will grounds backfeed through other sensors and give continuity readings to more than one pin location? Sorry, I did not have a chance to review wiring diagrams before replying to post.
I did replace the VVT pulley. What is the difference between blacktop and silvertop pulley? Grant from Battle Garage supplied the pulley, and I am indebted to him. He has been very helpful. Now if only he would move his operations from CA to PA all would be good. Is there any chance that somehow a blacktop pulley was sent instead of a silvertop pulley or was in wrong box from factory? Would this change valve timing and prevent starting? Any way to tell difference between the two pulleys?
I will be reviewing all as time and temperature permits, but will have a bias towards checking into things that are known to have possibly changed since car was last on the road: valve and ignition timing (due to new head gasket), missing ground or air leak (due to removal/ re-installation of drivetrain). Although it is certainly possible that AFM has just chosen this moment to go south, in past experience it is unusual for such a random occurrence to be the new found problem on previously working engine.
Will update when I have better info, thanks again to all, especially Battle Garage.

[BattleGarage_RS]

Hi Greg,

Thanks for the kind words

I actually ordered both a blacktop and silvertop pulley when I shipped yours out - the part numbers are different and I double checked before sending you yours. The only difference between the pulleys should be that the timing is 5 crank degrees more advanced on a blacktop. I could be wrong though, maybe it was the camshaft that has the dowell 5 degrees more advanced on the camshaft itself.

Regardless, even if your cam was 10 degrees off, I promise you that wouldn't keep you from even getting a 'pop' from the engine...you would just have a lopey idle or weak power, depending on if the intake cam was advanced or retarded 10 degrees by accident.

Check that your AFM is getting power - find the power wire and ground the other end of your DVM with the ignition on. Turn off the key***** and put your DVM in Ohms, check continuity between ground and sensor ground, and finally AFM output back to AFM pin on ecu. As for the AFM output, there should not be any backfeeding, that output needs to go to the AFM pin, and only the AFM pin on the ECU. If it doesn't you have a problem.

If you are still getting the same codes, I think there may be a weak wire on your AFM wiring, or connector. Even a massive vacuum leak won't keep the car from starting, it will just idle like crap. Make sure your plugs aren't fouled before doing anything though.

Grant

[jondee86]

Very often it does come down to something simple like a wire not plugged in. And always
worth trying a fresh set of plugs after prolonged cranking... especially if the plugs in the
engine are old and black. The thinner head gasket will have minimal effect on timing...
if you have the distributor set to around about where it was before you had the head off,
it should fire up. As suggested above, the engine may need a bit of extra air to get
started... which reminds me... make sure your ISCV is plugged in

Cheers... jondee86

[gregsterling0000@aol.com]

Small bit of additional information. Checked box new VVT from Battle Garage came in, factory genuine Toyota box with part number 13050-16010, which is correct for silvertop. I will get back out in the ice box on Friday or Saturday, will update as appropriate.

[gregsterling0000@aol.com]

Here is the email everyone know was coming. Intake timing was off. Old man eyes, bad lighting, low intellect all combined to create the perfect storm. When I installed it, I saw the two scribed lines and one of the two dimples, did not see the other dimple. I had the two lines lined up with the witness mark at 12 o'clock, and the dimple lined up at 3 o'clock to match correctly positioned exhaust cam/sprocket. The other dimple that I did not see was at 6 o'clock. Unfortunately that meant in the intake cam was off by 90 degrees. On top of that, the chassis to block ground strap had become loose while installing the it really feels a lot quicker, more responsive. The new VVT from Battle Garage works great, and car no longer sounds like a diesel! A bit chilly here in PA, but it was a blast driving around this morning, plan on some more miles tomorrow. Of course I had to have the top down, what fun would it be otherwise? Thanks to all for your help. I'll post some pics of the car in the next week or so for anyone who is interested. PS have a spare T50 box if anyone is interested, as well as some synchro rings. I put a lower mile box in with the BT flywheel. Shifted great, had a minor issue occasionally kicking out of first, trans shop said it was probably weak shift rail detent springs.

[BattleGarage_RS]

Greg,

Glad to hear it! And you are lucky you have a ST and not a BT...if that was a BT you could have bent your valves!