badboy!

I just brought home a 1988 10th anniversary RX7 TII. The dealer said it had low compression in the 4th and 5th something and that it is too low to start. Is this possible for an RX7 with only 79,500 original miles on it?? I bought it from the original owner and it is in excellent excellent shape! I need some ideas on what I can do or replace to try and get it started or should I trust the Mazda place and have the motor rebuilt?

thanks for helping out a Newbie!

Tony

badboy!

Replaced all 4 spark plugs because the old ones were covered in black carbon. Still no luck in getting it started. It turns over like crazy and I left a spark plug off in each cylinder and blew out a bunch of carbon and gas. I can smell the gas if I try to turn it over a few times but it just won't catch. What would be the next step?

thanks!

Tony

badboy!

The Mazda mechanic said that there were 3s and 4s in the front and 4s and 5s in the rear for the compression test. I just don't think that the compression is the problem for it not starting. I am going to try getting a timing light and testing the coils to mark sure I am getting spark. Any other suggestions sure would help......

thanks,

Tony

badboy!

Ok guys, I bought an Inductive timing light this morning and the Lead set of Coils were working just fine but guess what! When I hooked up the trailing coils I got no spark I am guessing since the light would only flash on the 2 Lead coils and not the trailing coils that somehow the trailing coils are not functioning. So now I really need to know where to go from here. Do I need new rear coils or is there something else I need to check??...... ANYBODY WANT TO HELP??

Thanks!!

Tony

badboy!

I finally got the car started! It is running really ruff and it smoked like crazy since it hasn't been running for almost a year. By charging the battery with a full charge and trying to start it for almost 10 minutes I finally got it started. I ran it and blew out a bunch of stuff but even after warming up the idle is going up and down and it will stall every once in awhile. The smoking stopped from under the hood and the rear of the car though after about 8 minutes. It was really low on gas so I put a couple gallons in it and I took a look at the fuel filter and I am not sure if it is original equipment but it is on the older side so I will be replacing that here shortly to see if that gets rid of the jumpy idle or not. Turbo seems to be spinning when I rev it up so it looks intact and functional. Any suggestions on what else to check? I really appreciate everyone posting on my thread and helping me out! Rx7s being new to me and all. I hope to provide the same support for the next newb who comes along!

thanks!!

Tony

Silver7

The hunting idle and low compression readings indicate there could be a couple of broken or cracked seals. If you doubt what the mazda mechanic told you then take it to a rotary shop for a second opinion. If the compression still comes up low then chances are you will need to rebuid.

badboy!

The car has less than 80k on it. I bought it from the original owner who took great care in the car. It is in excellent shape! After getting it started and blowing out all the old fuel, carbon, etc. there is no smoke coming out the exhaust at all. The oil is clean as can be. The radiator fluid looks fine but could use a flush. The temperature of the car after running it for 30 minutes didn't even reach the 25% mark. The oil pressure seemed fine while running the car. The mazda mechanic said that the compression is too low to start the car. Well, I got it started! It could very well have bad seals but with the low miles and maintenace history on this car makes me believe that it isn't. I will be testing other things before I credit what the mazda mechanic said. Once I change the fuel filter if the car still idles and runs rough then I will try getting my own compression tester and seeing what I come up with. Thanks for the help!!

Tony

Whizbang

its could have less than 80 and still have issues. Its a turbo motor. things like that happen. but its cheaper to not have the seal break off and damage things. Than it is too catch the low compression early, and rebuild it outright.

badboy!

I am going to buy a compression tool tonight and follow the steps on the forum for measuring it. Warm motor, Both top spark plugs pulled while testing, EGI fuse pulled and WOT throttle. Will post what I get! Wish me luck!

Whizbang

remember that the readings your will get are relative. Not actual considering the tool is meant for a piston engine, but it will be a good indicator of what you are up against. post the results in detail.

badboy!

Will do! The help is greatly appreciated!

badboy!

Ok, I bought this engine compression tester that has a pressure release valve on the side of it. I used this to test my compression tonight. I am really confused on how this turned out so I will put as much info on here as possible.

The car started right up today after finally getting it started yest. but it still has a slightly jumpy idle and will die everyonce in awhile plus the engine seems to run a bit rough. I pulled both of the Trailing/top spark plugs after warming it up for 10 minutes. I did the compression test. The rear if I DID NOT hold down the release button would pump up to right around 90 and stop. If I held down on the release valve it would only go up to between 40 and 50 as the engine was turning over. I had similar results on the front. It actually went up to 105 if I DID NOT hold down the release button. If I held it down the needle would jump up to the 50 and 60 range and back down to zero rapidly. So I am really confused at this point. What is the actual compression? I also noticed that there is a gas smell in the oil but the oil looks clean and is filled to the correct specs. Still no smoke coming out the rear of the car at all... I also noticed when I hooked up the timing light that the trailing spark plug coils were not firing at a rythum consistantly but almost spiraticallywhich I have no clue if it is normal or not. Even the main coils had a slight skip to them as the car was running. The timing seemed to look fine from what I could tell. So what is the next step here and is the engine hosed? Thanks!

Tony

jamespond24

iTrader: (13)

Compression looks low. 3's and 4's in the front with a mazda compression tester is lower, it should be in the 6's and up.

badboy!

This is not a Mazda Engine tester though so I have no clue which of the two readings is correct. Anyone know?

badboy!

Started it right up last night and drive it around the block. Turbo kicks in but the car dies at every stop sign. It seems to be a bit jerky also threw the power band. Still needing some help on what to look at next...

thanks,

Tony

badboy!

Help.... Help........ Help............

There is a Fat man dancing in my thread and he won't go away till I get some help!! I sure am glad my 2g DSM-T runs good!

Anybody live in the Houston close to the Katy area of Texas that wants to help me look at this?

badboy!

I replaced the fuel filter this evening and ordered new spark plug wires for tomorrow to put in. The fuel filter didn't really help even though it seemed like it was original equipment! Not by looks but by how hard it was to get off!!! Like I said before the car was garage kept and is in excellent shape so it is hard to tell what he has replaced or not. I will let you know what happens with the spark plug wires tomorrow. Still looking for advice on what else to check.

thanks,

Tony

badboy!

I replaced the spark plug wires and it got rid of ALOT of the misfiring!!! I am so close to getting it to idle good but I guess I need to go get an ohm meter to adjust the TPS correctly so I will go get it and follow the instructions on adjusting the idle from the forum. I will let you guys know how it goes.... Oh if I advance the timing all the way with a warm engine it almost doesn't die but once in a great while. Just to put the info in here. I know what you guys will say and that is adjust the TPS so I am on that!

badboy!

Is there a problem with the BAC if I can turn the idle screw around several times and it doesn't adjust the idle at all? Even with a warm engine?

Broken09

iTrader: (1)

unsure what compression tester you purchased but ifit holds a pressure more than likely if you look in the bottom of the line/hose that it comes with you'll see a small valve (Schrader sp? valve) In many of them this can be unscrewed so the compression tester doesn't hold the pressure, but will allow you to instead watch for three even pulses. You won't get an exact reading but you'll at least be able to watch the needle and see that you're either getting one good pulse and two weaker ones or in worst case you've lost a seal and you'll get one pulse spaced further apart. You can base when you should see the pulses based on the sound of the engine as it turns over.
Right now you're just spinning your wheels. It's totally feasible you have bad compression and the car runs. My first motor ran lumpy and idled low but would boost and had similar patterns to what you said while you drove it.

badboy!

Adjusted the TPS to specs and no help. Starting to think that all this is for nothing. Guess you will see this car in the for sale section real soon

thanks for helping guys.

badboy!

Update:

I got it to actually run and idle without dieing but the idle is a bit high(800-900 RPMs). I cleaned the BAC but I don't know if that helped or not and I played around with the timing. When I drive it though at around 3,500 RPMs or so the engine chokes and at about 4,000 RPMs it kicks back in like nothing is wrong. I did some reading and people say the secondary injectors may not be working correctly? Anyone else have any ideas?

thanks!

Whizbang

yeah, that is a classic hesistion. Might need some regrounding done.

basically so far, your car is a prime example of standard little problems FC's have.

badboy!

I will check/redo all the grounding. I did some reading on that and it seemed to fix some peoples problems. I will try some fuel injector cleaner also even though it may not help much. I may even get all the injectors cleaned since it still doesn't seem to fire exactly right.

thansk for the post/help!