I'm having some problems getting my motor to run correctly and my other thread isn't getting to far. So here's the deal

I rebuilt a b16a with stock everything. I checked the gaps of the new rings, they seemed fine. I clocked them according to how they were clocked in the helms manual.



My head has titanium dual springs/retainers/valves and stock b16 cams. Well when my car jumped timing before the rebuild, it bent two of the valves. So I took the head to a machine shop. The guy hot tanked it, replaced valve seals, three angle valve job and replace those two bent ones, with stock valves. I wasn't too sure about mix matching valves, but he said it'd be fine, so I accepted it.

I finally got the motor back together and everything hooked up. Now on cold start, my motor will crank right up. It'll idle about 1500, but it doesn't sound too bad. It'll run like this for about 7 mins then it'll drop down to about 200 and that's when it starts smoking from the exhaust ports, then it'll eventually just die out. And it won't start until I let it cool back down.

If anyone has any ideas what this could be, your help is greatly appreciated.

 

Ok it sounds dumb but I'm gonna ask about the simple stuff to get it out of the way. Is the car overheating? Do you have sufficient coolant in the car? What color is the smoke? Did you set the timing correctly when you put everything back together? Is the head gasket good and did you seal/torque everything properly?

 

No coolant leaks and it's full. It's not even staying on long enough to get to operating temp. The timing is correct. I've checked that too many times. Smoke is fairly normal color. No blue, white or black smoke. Head gasket is fine, and I triple checked all my torque specs. My spark plugs are new and gapped correctly, my spark plug wires are correct as well.

 

Hmmm... How's the compression? Are the rings good? Is the thermostat in good condition?

 

The compression is. 170, 155, 160, 160

The rings should be good, since they were brand new. The thermostat is the only thing I haven't tried. i'll probably pick a new one up since they are only about 6 bucks.

 

sounds like the cam timing could be out of wack. if you had the head shaved very much you will have to degree the cams since the honda marks only work at full height or near it. you still should double check your cam timing AND ignition timing. remember you set ignition timing at 750rpm with the jumper jumped and the car warm. the only other thing i can think of is the low idle is caused from the increase in spring pressure in the VT. more spring pressure means more resistance and more power loss. think about cranking up the heater and turning on the headlights. the idle goes up right? that's because the alternator puts drag on the engine when you tax the system. your springs could be doing similar. try turning on the heater and see if it idles up. the 1500 at start is correct so i'm thinking one of these above listed will help your closed loop warm idle out. i'd start with the heater trick just because it's the easiest.

 

I didn't have the head shaved at all. I appreciate it man. I'll go try these solutions, and let you know.

 

Well now I seem to be throwing code 3, which is the map sensor code.

 

did you get the map and tps wires switched around? issues with the map could absolutely cause the problems you describe

 

Well I've tried switching them around, and no effect. Maybe I just have a bad MAP sensor, or the wires going to them are bad.
And the rpms where at 1000 when I had the heater on full blast.

 

after it warmed up? that's within the ballpark if where it should be. thankfully for you MAP aren't too expensive. 50ish if i remember right

 

after it warmed up? that's within the ballpark of where it should be. thankfully for you MAP aren't too expensive. 50ish if i remember right.

if you are at 1000 when the engine is warm and the heater is at full blast, then drop to 200 if you turn everything off. well, you could try fooling with the TB screw but you might need the ecu map altered at idle due to that spring increase. that extra pressure is bogging the engine. i assume you used this VT for cams down the road. you probably could get by just running the fan all the time till you save up for cams. that way you aren't paying the tuner twice.

 

Well I replaced the map today, still the same thing. I used the same valvetrain before the engine was rebuilt, and it ran fine. And the only way it'll stay on long enough for me to get it warm is if I keep it around 2500 while idling. And also, I can crank up the car for two seconds, turn it off, then go to turn it right back on and it won't start. I don't understand, the only thing that is different in the car, is the wiring harness. I think I'll try another harness.

 

are you positive your cam timing is correct? line up the marks real quick and double check

 

I'm betting on this is the problem. I had similar issues with my head when I sent it to the machine shop to get the head resurfaced with 3 angle valve job done. The engine wouldn't hold the idle unless I kept above 2k rpms.

As soon as you mill the head beyond factory specs your cam timing goes crazy. You can do what I did and get yourself a set of adjustable cam gears and play with the timing.

I advanced my intake side 3 degrees and exhaust side 2 degrees and that solved my issues. BTW I would recommend running 91 octane or higher since the cam timing is advanced but then again I'm running a b18c1 engine so that's not optional

 

Well I'm gonna recheck timing in the morning, but I didn't have the head milled at all. Maybe he just did it without me telling him to.

Haha and I run 91 all the time anyway.

 

Back to the headwork, did you have the guides replaced also? If not, that would probably explain your smoking problem. Make sure the TPS and MAP are correct.


I don't think that reasonably stiffer valve springs would cause any issues. The ECU calculates a load value and can easily compensate accordingly. Just as if you were to change the weight of your flywheel. If the ignition timing is set properly, it should idle around 750 rpms.

For what it's worth, I ran my motor in stock configuration with Supertech Valvesprings & Retainers without any problems. My rotating assembly, although balanced, is also heavier because of the forged pistons & rods. This was at 10:1 Compression, OEM cams and OEM ECU. Idled fine, didn't smoke, AFR's were fine.

 

No I didn't have them replaced as well, but it wasn't leaking before hand. Would they just start leaking after being machined? Because I didn't think they needed to be replaced, but I could be wrong.

 

Well you stated that your timing belt skipped a tooth and you bent two valves, correct? If so, you should have replaced those two guides at the very least.

 

Yeah, that makes sense. Thanks for the help, I'll get on that timing tomorrow.

 

totally. ignition AND cam timing have to be correct. both of these need to be checked. it's not hard to be off a tooth if you dont install the timing belt according to procedure.

 

dont mean to change the subject, but his compression (170,155,160,160) numbers seem a bit low. is this because his rings havn't seated in fully yet , cause a freshly rebuilt b16a should be atleast between 180 or 190ish for compression. that cylinder with 155 is way low definitly losing compression alot, is that the cylinder that had the bent valves?

 

even if there was a small compression loss, it's so even that no single cylinder is suspect. the gauge is more than likely the reason for those numbers. only one cylinder had issues since he says 2 valves bent.