Rookie here with Vacuum issues possibly more.

[trailerparkzero]

First I got to say sorry about this repeat topic but i've spent hours reading post and i'm kinda lost now.
I dont know if this is good or bad but my problem escalated from being intermittent to all the time. Sometimes my baby would get high idle when warmend up then it was hard to start (flooded) when already warm. Sometimes this wouldn't and it would run fine other then a slight misfire. I wouldnlt normally drive unless it was running good but I left my bike at a friends so I had no choice. I went to start it this morning and the battery was almost dead. a couple silent tries and it started to turn and then started. Yes, I will make it to work on time today. I had to keep my foot on the gas to keep it running until she got warm. I started on my way when suddenly it went wide open racing up to 7k rpm before I turned her off in panic. Slowly turned over again and right off the bat it was wide open and I had to shut her down again. The third time it was fine, running ruff but not too much worse then normal. As it warms up the rpm keep getting higher and higher and sometimes it surging. I have no high idle at start and I used to. Another note about the high idle issue that when you rev the engine it is sluggish to rev back down. Bad fule cut solenoid?
I've replaced the TVSV, PVC which was bad, AAP diaphragm (old and dry but ok). I took off the HAC unit the one hooked up to the black nipple blows right out the bottom and the other three red nips including the capped port and plugged solid. I want to disable this but am still not totally clear on how to, it seems that there is more to it then just the vac advancing the dizzy. I reset the timing back to 5 before this happend as I was hearing a crackling (pinging) when accelerating while the engine was in its high running mode. The vac line i disconnected to set the timing does advance when i hook it back up it so it seems that it is ok.

I used the carb cleaner method to identify my vac leak with no avail.

Its running so high it makes trouble shooting stressful, I dont want to burn my cat or cause worse. Should I try to adjust idle to normal RPMs and trouble shoot the tvsv, AAP, other components that would couse this per FSM.

Some notes that worry me about this car. sometimes when i shut if off and the revs are in the right spot it nocks a little. not fully running on but just a few knocks. Sometimes I hear valve noise but others its gone? When the cars warm i hear a louder exhaust noise then normal only when throttle is given.

Thanks for reading and any help is much appreciated.

[Petros]

sounds like a big vac leak to me. check the power brake booster, if that is bad it will not show up in a carb spray leak test. Did you check your float level? if it is flooding it could also act like this, check the sit glass in the float bowl for correct level, if not you have to remove the top of teh carb and clean out the needle valve. does your linkage all work properly? what happens if you push the throttle plate back to idle when it is reving on its own?

Also, double check the routing of all the vac lines from the vac diagram for your car. the test for the HAC is easy, if it fails just route the vac lines as shown in the vac diagrams for a car without the HAC. The HAC does two things, both advances the timing and leans the mixture. It leans the mixture by bleeding air into the intake manifold, if it is bad it will act like a vac leak.

[xirdneh]

how about the throttle cable?
is it too tight or binding?
i would look at that
make carb butterfly valve is closing all the way to idle position
then have someone hold it down (at idle position) while you start the car
if it still races then you know its not cable related

[dlb]

the carb cleaner approach isn't one of my faves. it's not a bad technique but there are lots of leaks that you won't find using it, like broken diaphragms, worn out charcoal canister, etc. also, some areas are hard to access, like the carb mounting nuts and the intake manifold bolts. best to check those not just visually but to put a socket on them and make sure they're snug.

another culprit for difficult vac leaks is the phenolic spacer at the base of the carb. i haven't experienced it myself but i know others have found it to be crumbling away and a huge leak.

for the HAC, just disconnect and plug the vac lines going to it, including the port on the vac advance cans.

good luck, let us know what you find.

[marlinh]

This car wasn't driven much I assume from the mileage. Fuel deposits in the carburetor may be the culprit causing the sputtering and hard starting. I rebuild a carb from a car that sat for a long time. It was amazingly filthy inside.

Floor mats have been known to jam the throttle open. Make sure it is not interfering in any way, plus everything else mentioned above.

[trailerparkzero]

Thanks guys
peteros
I disconnected the brake booster and it fired right up and was running a lot better but it was still a little screwy so I think I have more then one problem. The gas level was at the upper flat of the sight glass. Im not sure how bad that is compared to being right in between. I will check this again next time I am having the flooding issue.

The linkage seems to be working fine. I just got the check in the mail to pick up that old carb if its still avail then i can put a new fast idle cam on. other then that all seems to move smoothly and return to its home when let go.

I tried the carb spray test again and i got some results. I swear I hit this place many times before but it def revs high when you spray in between the carb and the vale cover. A leak is coming from somewhere on the left side of the carb. I need to find the straw to know exactly where its coming from. Everything seems connected. I ran out of daylight before I got it pinned down but tomorrow is another day. dlb I will check the mount bolts before I go hacking into anything. If that dosnt solve it there is nothing left to do ecept pull the carb and check the gaskets. its my favorite way to learn "shit your pants and dive in"

Marlinh your right this car sat along time. When i look into all the nooks and crannys in between the carb and valve cover there is mouse/rat shit in every nook. I'm lucky they never made it in the car and didnt chew more then a few wires.

I

[Petros]

you might also check the manifold bolts, they sometimes back out because of the temperature cycling, you will have to bend the heat shield to get to the upper ones, the lower ones you can reach from under the exhaust manifold with an open end wrench (a bit of a PIA, I used a mirror to guide the wrench to the nuts). Before you remove the carb just snug down the 4 bolts that hold it down. 12mm socket and an extension should do it.

I bought a Tercel4wd once really cheap that also sat for a long time, it ran like crap and had a failed diff. Once I fixed the diff and the brakes I spent some time on the engine. the previous owner said the carb needed rebuilding. I found nine vacuum leaks, and a number of mis-routed vac lines, but it was only running on two cylinders. the vac brake booster hose was disconnected, starving to the two rear cycles of fuel because of the massive vac leak. ONce all the vac leaks were found and corrected, it ran great. I never did touch the carb on it.

[trailerparkzero]

well the bolts were a little loose and it seems like the RPMs aren't changing when I spray there but she still is not purring like I want her to. I think I have some significant carbon build up that is causing pre ignition as I am still getting pinging even with my timing set to five. Tho I cant rule out this is not caused by something else. When I hit it with a timing light the notch is not solid in time sometimes its a bit off. I'm not sure if that a dizzy issue or caused by another vacuum leak. I'm considering giving it the seafoam treatment in hopes to knock some carbon off the pistons but thats asking a lot. I think the next best bet would be to set the valve clearance. It dosent look too hard and could possibly be the source of my pinging.

I think it might be carbon build up because older folks are known to do this to cars because of all the short trips they take. They never take the car on long enough trips to get the engine hot and burn off the carbon?

[marlinh]

Have you pulled the spark plugs out to see what condition they are in? It will tell you a lot about the condition of the engine.

[Petros]

it may need the valves adjusted, but it will not affect ping or the way it runs. If the timing mark jumps around a lot could be a bad distributor, either distrib. bearings or pick-up is weak intermittant. Usually a wrecking yard distributor is a good bet, just swap them out (you have to reset the time, do it carefully so it goes back in the correct way, see the threads on this topic).

also, do the tests on the EGR shown in the manual, if this is functioning or connected improperly it could cause bad ping. Or just remove it and block off all of the ports.

Removing carbon might help the ping, but not likely that is the whole problem. It would be pretty rare for it to cause that kind of a ping problem, it may need to be de-carboned, but that alone will not cause it to be bad. check your EGR, and the condition of the distributor. There used to be shops that could test your distributor function for a low price (you have to remove it and bring it to them) check a NAPA store maybe? Or follow the service manual procedure to test the distributor function.

[trailerparkzero]

Well I finally got the parts in and got down and dirty. I took the carb off and found the source of my problem, the gaskit between the spacer and manifold had failed. Kinda hard to imaging how a path formed all the way threw it but some how it did. replaced that and pulled off my egr valve while the carb was off and moving the diaphragm did not change the flow threw it at all so it seems that it was bad. Not surprising the inside was caked with carbon. I bought a used dizzy off of ebay for $40 all the coils tested fine and it was very smooth. It needed a new cap.

I got it all finished and went to fire it up and she putter but it wont start. I tried switching back to the old dizzy with no avail. Checked all 4 plugs on both dizzys for spark and it was nice and hot. Last time I parked it about 2 or 3 weeks ago it was running realy ruff.

My battery compleaty died and when I went to pull it last weekend I found that it was boiling acid out of it and all over the place Clean it up the best that I could but the damage was done(some paint peeling). I will never leave a known bad battery in anything ever again and I suggest the same for anybody else.

Can somebody clear something up for me? if I have all four spark plugs out and hold my finger over the #1 plug hole and crank the engine over should it build up compression? It does when all three are in except #1. Does this mean that I have a blown HG between 1 & 2?

[marlinh]

Are you saying that you aren't getting any compression build up in #1 cylinder except when the other spark plugs are in? You should feel something even if there is damage between the cylinders. Is someone cranking the engine over with the starter or are you turning it over by hand with a ratchet? If you have had the distributor out you may have reinstalled it with # 4 on compression instead of # 1. The crankshaft would be out 360 degrees. You need to determine that by lining up the timing marks on the crankshaft and cam by pulling off the upper cover. The FSM will show the marks.

[dlb]

if you put a new dizzy in, i imagine that's the cause of your crank/no fire situation. it's probably just not installed properly. here's how i do it.

https://tercel4wd.com/forums/viewtopic.php?f=2& ... zzy#p61628

do that and try starting it again. to answer your last question, your #1 cylinder should only build compression on the compression stroke so make sure you are on that when you put your thumb over the spark plug hole. if you do this but still find you have no compression, get a compression tester and do that. if the one cylinder has no compression, it's most likely a valve failure. a bad headgasket usually manifests with two adjacent cylinders having poor compression.

[trailerparkzero]

I took the timing belt cover off and made sure I had the dizzy in right. It didn't help the car would only "run" with full throttle , it sounded like only one or maybe 2 cylinders were firing. I went and got a compression tester and had a friend help me when I did it. I forgot to tell him to give it full throttle when he did it so I think that why my results are so low. 1 & 2 came in at about 150 and 3 was 130 and 4 was about 125. My battery has gotten a little weak from all of the cranking I've done the past few days but it still is cranking over fine. I did the test with all 4 plugs out so I think my HG is ok since I do have compression in all 4.
or could this mean the HG is blowen between 3 & 4?

Things got worse my friend locked my keys in the car and I can't find my spare!

I need to find my spare, charge the battery up and retest. I need to be sure its bad before I go any further.

[Petros]

your compression sounds fine, but I have had a marginal head gasket that had good compression but still leaked coolant into number one cyl. but that will not keep it from running (and not likely your problem). I would double check the distributor is installed correctly, sounds like it could be 180 deg off, or a gear tooth off.

good luck